Summary

Even experienced builders make these wiring mistakes — and they're often what causes unreliable electronics down the track. Learn what to avoid before it costs you.

00:00 Hey everyone, welcome to today's webinar.
00:02 I'm Caleb here at High Performance Academy.
00:04 It's great to have you along with us.
00:06 Today we're going to be looking at just some common wiring mistakes and issues, things that I've just sort of come along across in my time as a automobile electrician.
00:16 Some of the common things that I think people just sort of gloss over a bit too quickly or just don't think about enough and it can cause some future issues.
00:25 So, today we are live at the moment, but if you need to watch this at any other point, it is recorded and will go up onto the website.
00:32 So, if you do need to duck away, that is okay.
00:34 We can watch this at another time.
00:36 For now though, if you joining us today, I'd really do appreciate it.
00:39 And if you stick around to the end, we will have the Q&A at the end.
00:43 And today specifically, I think that'll be a good one because I'm just going to kind of go over a list of things that I've got here, some common issues and problems.
00:51 But I particularly want to hear some problems and issues that you guys are facing or have faced, seen other people do, and we'll have a chat about that.
00:58 So, it might be a bit of a shorter webinar today going over this list, unless I get derailed and start talking too much, but I'll give you a bit of a heads up later on when I'm getting near the end and you can start getting those questions in.
01:11 So, let's get stuck into it.
01:13 And I think one of the main issues that people overlook is undersizing wiring and wire gauge, particularly for long stretches of wiring.
01:26 So, most people I find, they will look at their specific wire that they have, whether it be just generic PVC wiring or they've gone for a Tefzel, and they will look up a amperage chart that most wiring brands, companies will have some sort of amperage chart.
01:42 And they'll look at the specified amperage for that size wire and just go, that's what this wire can handle.
01:49 That's within my limits, so I'm going to run that.
01:52 Problem happens though, when we're running, especially long distances or long lengths of wire.
01:58 Common issues or common places this happens is particularly with fuel pumps or say thermo fans, depending on where your battery and everything is situated.
02:07 Sometimes if you have thermo fans in your boot for a rear-mounted radiator setup.
02:11 The problem is you may have a wire gauge in mind that is on paper rated to the above the max of your fuel pump or thermo fan.
02:22 But the fact is on that long length of wire, you do have resistance of that wire.
02:27 And when you get a long length, it does add up.
02:31 And this resistance causes voltage drop when you pass a current through it, especially when it's a high current, things like a fuel pump or a thermo fan.
02:39 So, what happens is while you may be not drawing too much current and essentially burning out wire, what will happen is a voltage drop at the end of that wire.
02:50 And what your fuel pump is saying is actually considerably lower than what it should be saying.
02:55 Whether it's the 12.4 volts when you're just sitting stationary, not running, or 13.8, 14.2 when you're running.
03:04 And this is particularly important, fun especially with fuel pumps, because your ECU is interpreting fuel pressures and things like that based on voltages.
03:13 And if your voltage is dropping in places and things aren't quite up to par and what everything is expecting, you can run into some issues that way.
03:22 Also though, if you do get enough voltage drop, that can then cause a snowballing effect with heat and current, and you end up getting to a point where you've over-currented that wire that you're actually looking for.
03:34 So, when you are sizing your wire for a particular wiring project, make sure you do take into account the wiring length especially, and do some calculations on voltage drop.
03:44 You can find calculators for this kind of thing online quite easily.
03:46 And also things like the data sheet for the wire that you have, as well as a general spec for current.
03:54 It should tell you as well the resistance per feet or per meter, and you can use this in your calculations.
04:00 So, we'll just touch on those amp charts that you find.
04:03 They are definitely helpful, and it is something good for just a quick lookout to gauge where you need to be.
04:08 But they're gauged at a certain data set, so, certain temperature, certain length of wire, all that kind of thing, and that's the given amperage for that particular point.
04:21 So, if you have a situation where you're running your wire somewhere that's hotter, in an engine bay somewhere, or like the example I've given, the long length of wire, these amperage charts need to be sort of taken into consideration, and you need to actually do the calculations yourself just to make sure.
04:37 The next point I've got here is when you are sizing up your wire and taking into consideration the amperage rating of a component, things like inrush currents for thermo fans especially, and pumps, and most motors, that kind of thing, while they do have a set current limit for their highest working pressure, or a fan when it's at its highest speed, pushing the most air, they do have also an inrush current when they actually need to start up.
05:08 If you think about trying to spin a big water wheel or something, it needs a bit of effort to really get that going, and that can cause a certain inrush of current that may be particularly higher than what you're wiring, what you're expecting the constant current to be.
05:25 So, you do have to take that consideration as well.
05:27 These are a bit more relaxed, I guess, just because you are only drawing that current for a very split second of time, so, it shouldn't cause any dramatic issues, but it can cause issues with things like tripping breakers, or PDM outputs, that type of thing.
05:44 I just had a thought on that as well.
05:47 What was I thinking about? I'll come back to that maybe.
05:51 Mid-thought, I've lost that already.
05:53 Just going on from that, power distribution and circuit protection.
05:58 I've seen this way too many times.
06:01 It kind of irks me a little bit, but fusing your circuits too far away from the power source.
06:07 So, a bit of a contradiction to what some people might think is we're fusing to protect our wiring, not to protect the actual component itself.
06:17 So, if you have, say, even just an ECU, that the rating is 10 amps, that doesn't mean that we're just gonna run a 10 amp fuse and that's the end of it, because we're not actually fusing for the ECU.
06:32 And also we want to run our fuse at the very closest point to our power supply as possible, mainly because what we are trying to protect is our wire.
06:40 So, having it at the initial point for the wire is the best bet, but also the amperage rating, what we're trying to take into account, we want to size our wire to handle that max current of the component.
06:53 But then in a situation where we have a short circuit or the component going bad, we want the fuse to break before we hit the limits of that wire.
07:04 So, we need to size appropriately.
07:05 If we've only got a wire that's capable of 10 amps, we're pushing the limits as far as what the ECU will pull through it.
07:12 That fuse is not necessarily going to protect our wiring.
07:17 So, when we are thinking about this sort of thing, I'm just trying to think of a really good example.
07:22 As far as being too far away from things, I see it a lot with fuel pump upgrades.
07:28 You might have someone's done the right thing and added a relay in and beefed up the power supply to their fuel pump if they're going an aftermarket fuel pump, but they've run the fuel pump fuse, the new fuse for the upgraded circuit, all the way in the boot where the fuel pump is.
07:44 And they've got a long length of wire going all the way back to the battery.
07:47 And essentially anywhere before that fuse is unprotected.
07:50 And if you have a short circuit anywhere between that fuse and your battery, that is, as I said, unprotected.
07:56 It can just continue shorting out until it's burnt out.
08:00 It'll keep drawing maximum current until it's either melted the wiring itself, or cause a fire, which is even worse.
08:09 So, make sure you are running your fuses as close to your power source as possible.
08:13 You'll see most OEMs are doing it this way.
08:15 They'll have a larger fuse covering most of the circuits near the battery itself.
08:20 And then they'll split out to smaller fuses in different areas.
08:24 But they will be making sure that the wiring between those points is capable of handling the current around that fuse point.
08:31 Because if the wiring can't handle the current of that fuse, then that fuse is essentially going to be doing nothing and your wiring will burn out before your fuse will actually do anything.
08:44 So yeah, the main thing to take from that is you are fusing for your wiring, not for your actual component.
08:50 A lot of people sort of think, you know, you're fusing just in case your component is causing an issue or there's an issue in your component and you want to save it.
08:57 The main reasons you're going to have high current passing through, say an ECU or even just a fan or something like that, that component's probably faulty as it is and that's what's actually causing the high current.
09:08 So, what you want to protect is your wiring before it from burning out because of that high current.
09:13 At that point, there is no saving the component, but there is saving your car and anyone else around you when that accidentally catches fire.
09:21 So, that's why, yeah, that's the main reason we have fuses is protecting that in-between point.
09:28 Most components, especially things like ECUs, will have some sort of internal circuitry that will break if there's, you know, a high current passing through it, that type of thing.
09:38 But more often than not, yeah, if there is a situation where your ECU, any component is drawing more current than what is specified in the data sheet, it's most likely an issue with that component and it's going to be a throwaway anyway.
09:52 Continuing on with our fusing, what have I got here? Yeah, running accessory circuits straight off the battery with no protection at all.
10:00 I've seen this way too many times, mainly people putting in things like driving lights, spotlights, that type of thing, because the battery's there nice and convenient in the engine bay, that was run straight off without a fuse.
10:12 And also not running a relay with that type of thing.
10:15 So, with our high currents, I do have a webinar that I did just recently on relays and why we use them.
10:21 When we are trying to switch that high current, we ideally want to use a relay because when we're switching such a high current, whether it be for driving lights or maybe a thermo fan, typically, the switches that we have can't handle that high current.
10:35 If you're talking about the, you can get toggle switches that can handle up to 20 amps, that type of thing, they're generally okay, but more often than not, we don't want a big bulky toggle switch in our car.
10:45 So, we might run something smaller, but they're only rated to say milliamps and you really need to run those switching a relay, which then switches that high current power.
10:55 The other issue I see a lot when using relays as a bit of confusion as to where the fuse goes for the relay.
11:01 I've seen quite often fuses going on the switching circuit for the low current side of the relay, sorry, and no fuse on the main current side, which is the complete opposite of what we're really looking at.
11:14 So, making sure that you've got your main trigger, your main, sorry, main current side of your relay fuse.
11:21 More often than not, if you're running a relay for thermo fans or something with an ECU, you will generally be using ignition to your switching circuit and that'll often be fused at some point as it is.
11:35 So, you generally don't need to worry too much about fusing, but do make sure that there is a fuse in there somewhere.
11:41 What else have I got here? Using relays, that's sort of the main big one I'll talk about there.
11:49 That comes into grounding then.
11:51 Grounding is another place where we see numerous issues, not, so much issues that cause fires, that type of thing.
11:58 It does if you don't size your ground appropriately, which is one of my points here.
12:03 When you are sizing your wiring, make sure you're doing it on both the ground, your return, as well as your power.
12:09 I do often say, people will run a decent sized wire for their power going to say a fuel pump and then the ground wire is just, it's short, but it is very small and just not appropriately sized.
12:21 Make sure you're doing both, as electrical is a closed circuit.
12:25 So, there's a circuit there, it's got to go all the way around.
12:29 But the problem I was getting to there was ground loops and ground offsets.
12:35 It's a pretty big one, especially when it comes to ECUs and trying to get good signals from sensors.
12:44 Ground offsets and ground loops are notorious for interfering with these.
12:49 Do have another webinar that goes into that quite a bit deeper and talks about how it happens, why it happens, how we can kind of avoid it.
12:55 The biggest things though, you making sure that you use your sensor grounds from ECUs and PDMs.
13:02 They are there for a reason and it is because of ground offsets and causing interference.
13:07 And also when it comes to ground loops, making sure you're only grounding to one point with a component, don't ground then between another component and vice versa.
13:18 The biggest issue is, you see it a lot with audio equipment because you'll have say a amplifier that's grounded and then a head unit that's grounded.
13:26 But then also there might be a RCA cable or an auxiliary cable that's going between the two, has an earth running through it and that creates an earth loop.
13:35 I see it a lot with home theater stuff and audio equipment with musicians and things because they have all these different components that have their own grounds going to a wall, but then they also have connections between each other and they have grounds and it just causes a massive ground loop mess which causes a lot of interference.
13:53 So, making sure that you just have a good singular grounding point for each component, don't go running grounds to all different locations.
14:02 And then the ground offsets, making sure that your critical sensors are grounded to a single reference point, which generally will be your ECU sensor ground.
14:13 And touching in that with the signal grounds, making sure that you can avoid things like ECUs and PDMs sharing their ground with a high current ground circuits, things like starter motors and stuff like that, making sure that the current from those isn't going to influence.
14:31 I do have another webinar that touches on that and talks about how the ground offsets can be, they are particularly bad when you have a high current passing through them.
14:41 The other thing is I've touched on the ground strap or cable being undersized relative to how much power you actually have.
14:48 A lot of people, when they're upgrading, say an alternator, putting in a bigger sound system or just putting in a lot more electronics, they'll upgrade their alternator, bigger power cables, that type of thing, but then forget to do their grounding cable.
14:59 As I said, it's the same thing all the way around.
15:02 You need to create a good circuit.
15:04 So, making sure that those grounds are beefed up and suitable for the power that is out there.
15:09 That's actually going to be passing through them.
15:12 Keep on going on grounding as well, making sure that you have a good ground.
15:17 I see it way too often.
15:19 You think it's just common sense kind of thing, but unpainted metal, no corrosion, that type of thing.
15:25 You basically want, if you have say a cable lug, that's going to be your ground.
15:30 You want the flat surface of that to be making really good contact with the flat surface of a metal panel or a metal object like your head or engine block, without any rusted metal that's flaking off or paint, primer, that type of thing.
15:44 You want that good metal to metal contact.
15:48 Because one thing I need to note on that, you can get situations where if you're just probing out with continuity, you can get your multimeter buzzing and giving you a continuity true statement.
16:00 Even though there is actually a bad ground, there will be enough, sorry, lack of resistance that it will show essentially a ground or a connection.
16:10 But in fact, you do have enough resistance there that it could cause issues when you start passing current through and especially high current.
16:16 So, making sure that you have a good, proper ground is another, even though it's probably, you hear it all the time, it is often overlooked.
16:23 And I see those issues rise up heaps and they cause weird issues as well.
16:28 Things like your ground offsets and that type of thing.
16:30 They often show as just misinterpreted readings for sensors, that type of thing.
16:35 Lights playing up weirdly.
16:37 Not necessarily faulty, this doesn't work, that doesn't work, this isn't doing what it's supposed to.
16:42 It's more little quirky things that make you scratch your head and wonder what is going on.
16:46 Grounds, always check them.
16:48 And they're generally my first point when I'm looking for a particularly unusual fault.
16:54 Also with that, I find a lot, I see a lot in older cars, especially when trying to find a good ground.
17:00 Make sure that if you are grounding to a metal panel on a body, that it is actually connected to the rest of the body in a good way.
17:09 Particularly with older cars, I've worked on a lot of Datsuns, they are just prone to rust.
17:13 And you'll find you might be connecting to a really good bare bit of metal that looks healthy, but where it's actually connected to the rest of the car, where it's spot welded, those spot welds can be corroded or just anywhere in there can be corroded and you're actually not getting as good a connection as you might think to the rest of the car.
17:28 Which can pose a really big issue if you're grounding a battery in your boot and then you have another ground cable from your chassis to your engine.
17:37 If those points aren't connected by good metal in between, which is very common for Datsuns to not be quite nice, when you start passing high current through like a starter motor, it can cause issues.
17:49 And that's where you generally have a situation where you don't get cranking and it's just starts clicking the starter motor because you've got too much voltage drop and not a good enough ground back to your battery.
18:01 Easy way to sort of rectify this and see if you are having a problem, get yourself some good quality jumper leads and just connect a ground from your battery directly to say your starter.
18:09 And that'll tell you pretty soon whether your existing ground is not up to par.
18:15 Continuing on with this, I've got connectors and terminations.
18:19 Big thing, you kind of hope it's just not something you're gonna see, but things like scotch locks, wire taps, some people call them like vampire taps, the ones where you generally just squeeze the plastic connection, whatever it is, between two wires and it'll bite into your wire and create a great connection.
18:40 Say that sarcastically, because it generally, if it is a good connection, it's only a temporary good connection.
18:45 They're one of the biggest causes of bad connections and just headaches that I've ever seen in my life as an auto electrician.
18:53 A lot of the time, some components even come with scotch locks to install them.
18:59 And people will just assume, that's what's supplied with the product, so, I'm gonna use that.
19:03 And you get OEM and factories that are adding on aftermarket gear and they just wanna get it done as quick as possible, use the equipment that's there.
19:13 I see it a lot with trailer plugs.
19:15 They, especially back in Australia, where I'm from, they're a huge problem where they'd get fitted at the, sorry, what am I trying to say? Not the factory, the store that you buy in your car.
19:31 They would get fitted there and it would just be done as quick as possible.
19:34 And they generally scotch locks that just go into your lights.
19:37 And you'd see it all the time where people are having problems where their lights aren't working, their trailer lights aren't working properly, trace the wiring back, and more often than not, there's some scotch locks there just causing issues.
19:46 So, if you do see scotch locks, straight away, I say just replace them and do a proper connection and then go on diagnosing if there's more problems.
19:54 But chances are that's going to be your biggest issue.
19:58 Going along with poor connections, crimping terminals with just generic pliers and that type of thing.
20:05 Unfortunately, I do see it quite a bit.
20:07 It is tempting, especially when the price of some tooling can be quite ridiculous.
20:13 But I do find these days, especially for a cheap set of crimpers, doesn't really, they're pretty good.
20:20 I've had really no issues with the cheapest sets of crimpers.
20:25 The, what am I trying to say, the F-type or the W-type, you know, your ones with the folded in tangs.
20:30 Generally, you can get away with just generic ones of those.
20:33 They'll do pretty much most of your crimps that you need to do out there.
20:38 Even things like your Deutsch connectors, even if you don't have the proper Deutsch crimping tools, I do highly recommend it, especially if you're going to be doing more than a few crimps.
20:49 But say if you're just repairing a Deutsch terminal, Deutsch connector, you can get the stamped or F-crimp style.
20:56 So, I do recommend getting those to match the tooling that you do have, rather than trying to make do with a vice and a punch or a hammer and pliers or some other weird tool or rock on the ground.
21:08 Use the correct tooling where you can.
21:11 There's a reason why there's correct tooling for terminals.
21:13 They do have sort of specifications as to how they crimp together and that type of thing.
21:17 So, generally keep to it as much as you can.
21:21 On saying that, sort of a bit of a caveat, I guess, is a lot of the time those cheaper universal crimping tools for the WFB style crimps don't have the rounded crimp for doing seals on some particular terminals.
21:37 You can get away with using the FBW style crimp on the seals.
21:43 Just make sure you're not going too strong with that, not going too deep.
21:47 They don't really need to bite into the seal or really crimp around it really tight.
21:52 They just need to create a bit of a hold.
21:54 And you'll find, even when you crimp them with the proper round crimpers, it doesn't look like they have a really good hold, but it's enough to keep the seal there and keep it retained.
22:03 So, that's all you're really looking out for.
22:04 You're not looking to make a electrical connection where you've got to actually crimp into the insulation or seal.
22:10 So, you can get away with that using the different style crimper, the universal style.
22:15 Just make sure you're just going a bit easy and definitely do a test crimp and make sure that you're not crimping into insulation or piercing anything like that.
22:25 Another one is not having strain relief.
22:29 It's a big one I see with ECUs especially.
22:32 People will run a loom.
22:34 I see it a lot with pre-made harnesses, like off-the-shelf engine harnesses, that type of thing.
22:40 Someone might be mounting their ECU in a not, so common area and it's a little bit out of reach for what the original loom or the aftermarket loom had in mind.
22:50 But a customer or just the person using it might find that they can kind of stretch the loom a little bit and really get it to sit where they want.
22:58 But at the end of the day, putting that strain and tension on your wires is a sure way of having a failure.
23:05 When you start getting vibration in a car especially and heat and that type of thing, that tension on your wire is going to cause damage in the long run, particularly at the crimping section of your terminals.
23:15 But it can also cause things to work loose and terminals to bend and that type of thing deform and just cause absolute headaches.
23:24 I find it really annoying, particularly when you have say a amp seal connector where when you disconnect the locking tab, that unlocks all of your terminals.
23:37 And if you have a lot of tension on your harness and you're trying to just de-pin one terminal, it's really, really, really painful when you've got all that tension on and basically all your pins want to start trying to de-pin themselves just because there is too much tension and someone tried to stretch the harness too much.
23:53 So, make sure you do have that bit of strain relief in pretty much everything with your wiring, just running along a section of say your chassis or around your engine bay.
24:01 But as well, when it comes to actually terminating to a component, make sure you have a bit of slack there, some strain relief, so nothing's being pulled on and causing issues.
24:13 The next one I see a lot is using the, they're just the bullet and spade type terminals.
24:22 They are a good connection, they work, but the problem is they don't really have a locking mechanism in them.
24:28 And I find a lot sort of plays hand in hand with that no strain relief situation.
24:33 If you have just a little bit of tension on that wiring and you've got one of these insulated terminals that don't have any kind of locking on them, it only takes a little bit of vibration, heat to make a bad connection and have them disconnect when you really don't want it to.
24:47 So, making sure you're using good connections is a number one thing.
24:51 When it comes to, especially in your engine bay, that's I think the worst for it.
24:55 When in your cab, you don't really have the environment where things like your engine moving separately from your chassis to cause as much vibration to make things come loose.
25:06 So, it's, I'd say it's a bit more acceptable, but especially in your engine bay, make sure you are using a good connector type, especially, you know, Deutsch amp super seal, that type of thing.
25:15 They're not relatively expensive, so, it definitely is worth it.
25:20 Also, when it comes to moisture as well, when you're in an environment under the engine bay, you can quite easily get moisture splashing up or even just condensation over time and having a good weatherproof seal connector is gonna save you a lot of headaches in the long run.
25:36 And what else have I got here? Talk about physical routing and protection, sort of a, it's not, so much common sense, but you know, just running your wiring loom away from things that are gonna be a hazard.
25:53 One of the biggest, biggest things I've seen is particularly in the drift scene when you get cars that have been absolutely slammed and heaps of camber and the tires are rubbing up in the guards.
26:03 Some people don't think about the fact that the wiring is often running in those guards, particularly with, you know, Nissans, the Silvias, that type of thing.
26:12 They have their main harness running up there under the wheel arches, and it doesn't take much for that wheel to start rubbing through and you'll find cars just cutting out because they've rubbed through and it doesn't cause much of a, you know, issue, you know, there's no fires, that type of thing, but it will just, you know, make a cutout at random times when you least really want it, maybe in the middle of a corner, that type of thing.
26:33 And it goes without saying, you know, keeping away from heat, I see it too much as it is, you think it's just something that people wouldn't do, but running wiring looms really close to exhaust to the point where they're basically touching and I guess to the point where they do touch because insulation starts melting and dripping onto exhaust, not only is it electrically bad, but also you can, the insulation can start burning on the exhaust and then cause the rest of your loom to burn.
26:58 And that extra heat in your loom will actually, it essentially de-rates your wiring, as I was saying with passing current through long lengths of wire, that extra resistance.
27:09 When you heat up wire, it increases the resistance.
27:12 So, the more you heat a wire up, essentially the less amps you can safely put through it.
27:17 And it becomes a bit of a, again, a snowball effect where if you've got that extra heat, you're passing too much current through, that current will actually heat the wire even further and it just keeps on snowballing until you get to a situation where you're hopefully blowing a fuse that's been placed right, or you're melting wiring.
27:34 Another one, I see this all too often is not using grommets properly, rubber grommets, or even just some sort of proper protection around metal objects and especially pass-throughs for firewalls.
27:49 We always got to remember protection.
27:51 There is a reason for it.
27:53 And I've seen, again, back to the running upgraded wiring for fuel pumps, especially running a larger gauge wire from the battery in the engine bay all the way to the boot to the fuel pump.
28:04 And a lot of times I see it being passed through the firewall just poked through past an existing grommet that I could have gone through.
28:12 And it's even worse.
28:13 I can think, I just keep picturing one in particular.
28:16 It was an S13 and it was, the wiring was run all the way from the boot to the engine bay.
28:23 And the fuse was at the relay in the boot, battery was in the engine bay.
28:27 So, essentially anywhere along that wire that short circuited would have caused a high current situation to the point where there's no fuse to protect it and it would have burnt up.
28:37 And there were just points where it was going through a firewall, pushed past a grommet and contacting the harsh edge of a firewall.
28:43 So, make sure you're using some sort of protection going through those situations, even if it's something like the split conduit or your flexi braid, making sure that it is protected.
28:53 But more importantly, as some sort of rubber grommet, there's heaps of different types and sizes out there and it's cheap insurance.
29:02 Occasionally, I don't really see it causing huge issues, but zip ties being pulled ridiculously tight.
29:08 They're there to sort of hold things in position and not to absolutely choke your wiring.
29:12 Doesn't matter if your wiring lacks it.
29:14 You just, sometimes I can see it actually, particularly with the PVC coating wire that isn't quite as strong.
29:21 Zip ties that are pulled, so tight that it rubs a little bit and actually abrades through your wiring and that's just going to cause more issues in the long run.
29:30 I think that's probably most of it for the physical routing.
29:34 The heat, make sure you use some sort of heat sleeving if you can't get away from that heat.
29:39 There are situations where you might have to run your wiring close to an exhaust.
29:43 You might be doing wiring to say, I don't know, a boost solenoid or exhaust temp, exhaust pressure, back pressure sensor or something like that.
29:54 You might not have a lot of choice in getting at least close to the wire, to the exhaust, sorry.
29:59 You can use a heat shielding, whether it's a sort of a solid heat shielding or even a, what do they call it? A flame resistant coating.
30:10 You get the kind of like silicon and fiberglass coating often used for mainly for plumbing, but you can run that over your wiring as well.
30:17 And I've done it many, many times.
30:18 I come from background of building fire and emergency vehicles and as a part of that, I basically had to sleeve the entire truck's wiring loom in fire sleeve.
30:28 It was a painful, painful endeavor, but being a fire truck, it was a necessity.
30:36 I'm getting sort of close to my end of my list here.
30:40 So, hopefully you guys have started getting some questions in.
30:42 If you haven't, get them in right now because I want to make sure, I think that's probably going to be the biggest part of this webinar is just answering some of those questions.
30:49 Before that, I've just got a couple of last points here.
30:53 Mainly with signal and sensor wiring, particularly with your CAN bus and your ECU inputs, making sure when you have your twisted pair for CAN bus, not, not untwisting unnecessarily.
31:07 You will have to sometimes untwist a little bit just to get through a connector, that type of thing, and to splice in for another CAN node, but making sure that you're not, you know, untwisting a unreasonable amount and going too far back.
31:20 Or what I like to do in that sort of situation is I'll untwist what I need to make a good connection and get a good crimp or whatever I'm doing, and then retwist it as much as I can before the connector or splice point, just ensuring you have that twisted pair as much as possible.
31:35 The more you have the twisted pairs, the pairs twisted, the more likely you are to negate the influence of noise.
31:46 And it's not just with CAN bus.
31:47 This is the same with things like your speed signal wires from the engine or from wheel speed sensors, making sure that you do have as much as you possibly can as a twisted pair and shielded as well, particularly for those sensors.
32:03 Speaking of shielded, the shielded grounds, I see it a lot causing issues is grounding shield at both ends.
32:11 The main reason we don't do this is because it's a classic example of causing a ground loop.
32:18 You've got a component that's grounded at one end with its own ground, a sensor or something at the other end that doesn't actually need its own ground, it's grounded through the ECU, but then your wiring is grounded in two places there and creates a ground loop through the shielded wiring.
32:35 And basically when it comes to shielded wiring, you don't actually need a full circuit.
32:40 The idea isn't that you're creating a circuit, you're just creating a path for electrical interference, magnetic interference.
32:48 And because that is essentially in the air, it's not actually in the...
32:53 What's the best way of saying it? Electromagnetic interference is a field around your wires and other components.
32:59 So, it doesn't matter if you've got a complete circuit or not, as long as that the noise has a path to ground somewhere that it can get drowned out and absorbed by an existing circuit.
33:14 So, make sure you just have that one ground when it comes to shielding.
33:17 It can be, sometimes you might have a situation where you're adding in a circuit or adapting to someone else's wiring.
33:24 It does pay off just to check where that is grounded and make sure if you disconnect that ground, you lose continuity to ground.
33:31 Make sure that it isn't already grounded in two places and isn't wrong to begin with.
33:35 Don't assume that the work that you're adding to or that someone else has done is actually good in the first place.
33:44 The other thing, probably the last thing is just workmanship and processes.
33:49 Making sure that once you have created a loom or just even just a small section of harness, making sure you do continuity check just to double check, especially with connectors.
33:59 I am guilty for it.
34:00 The amount of times I quickly wire something up and pin out a connector, go to plug it in and realize I've mixed up my pin out or just swapped a couple of wires around.
34:10 A quick continuity check with a multimeter really saves a lot of headaches and it can be the difference between plugging something in and it working or spending three hours chasing down a weird issue.
34:22 And yeah, it's cheap insurance.
34:25 And also not documenting, I'd say it a lot, is making sure you document what you're doing, even if it is just a quick fix or a small harness or just anything in particular with wiring.
34:36 My general rule of thumb is I just start documenting.
34:39 I run a list down of the existing wiring or what I need to do, what needs to happen, wire colors, what I can reference.
34:47 A lot of the time you'll look at things and think, yeah, I'll remember that.
34:49 I'll go back to my bench.
34:50 And then you get there and you've forgotten and maybe that wiring's gone now, it was the old wiring.
34:55 It just pays to write things down.
34:57 And not only that, if someone else has to come to your work later on, if there is some documentation there, it makes it, so much, so much easier.
35:04 Take it from someone who has taken over a lot of other people's jobs and come into work halfway.
35:09 It's the biggest pain in the ass when the previous person hasn't documented it properly.
35:15 So, I think that sort of covers most of the common issues that I've found in my time, just the ones that are really easily avoidable, I guess.
35:24 But let's get into actually some questions now.
35:27 I see we've got a few here, which is great.
35:29 So yeah, hopefully we can delve a bit more into things now.
35:33 Before I get into the questions, I will just mention, we do have the 1000 horsepower 2JZ competition going on at the moment, the giveaway, free to enter.
35:43 You get more entries for VIP kits and that sort of thing.
35:47 Definitely jump on that one.
35:48 I wish I could, unfortunately I can't because I work here.
35:51 I love my JZ engines and Toyotas since I was a kid.
35:55 So, I'm really happy to see that going ahead.
35:58 And also jumping on our site and checking out the build section that we've got running now make sure you get on there and actually put your builds in.
36:04 We're checking it out all the time and occasionally we're going to be start doing, checking over builds and featuring them in webinars and that type of thing.
36:13 So, let's get back into, let's actually get into the questions.
36:17 Got Steven Sporting 3943.
36:21 If I mispronounce your names, I really apologize.
36:25 Do you recommend ground switching or positive switching when doing custom switches and or relays? Also, how do you feel about the butt connectors with solder inside them? That's a funny one that I will, it's convenient that you mentioned that now, but first up when it comes to ground switching or positive switching, honestly, either way works just fine.
36:46 There's no real issue with doing either way.
36:49 There are advantages to doing one or the other.
36:52 I sort of, I try and stick to ground switching.
36:56 I find it just makes things a little bit easier and cleaner as far as wiring, particularly if you have a big group of switches that are switching multiple different things, you can then just ground all those switches to one point near the switches and then just having your signal wires going to whatever.
37:13 So, that kind of just, it's kind of a, just makes things a little bit easier and neater.
37:18 You will find things like MoTeC PDMs, their signal inputs will only take a ground.
37:25 So, you need to ground them.
37:28 They kind of defeat the purpose of my making things easier situation because you do need to run the, they have a signal ground that they use.
37:36 So, you need to run that signal ground to your switches and then run it back for the signal.
37:40 But as far as the recommended ground versus positive, really, yeah, there's no right or wrong.
37:48 They have their advantages and disadvantages.
37:51 You often will find that you'll be doing sort of a combination as well.
37:54 It's a big thing I find with relays that that's probably a common mistake that I see a lot is running a constant 12 volt to a relay.
38:02 And then you have almost all ECUs will negatively switch things like relays for fans, that type of thing.
38:09 What you have in a situation is because you've got constant 12 volt going to your relay, a lot of ECUs, not PDMs, but ECUs and components will actually go to a ground when they're turned off.
38:20 They'll default to ground and that will actually turn things like your thermal fans on.
38:24 See it all the time with aftermarket ECU installations, turn the key off and the fan's just going full bore.
38:31 It's because there's a constant 12 volt to that relay.
38:34 In that situation, we wanna use ignition or a switched 12 volt and then have the negative switched by the ECU.
38:40 So, essentially you are switching both the negative and positive.
38:43 You're just using different scenarios, I guess.
38:46 So, the positive side is your master switch and then the actual situation switching is done by ECU.
38:55 So yeah, there's no right and wrong as far as positive and negative.
38:59 It's just they all have their situations where they work best and they can create a neater or a more convenient wiring loom.
39:06 And as far as the butt connectors with solder inside them, I've just started doing, I've got a heap of wires back at the workshop that I've done a heap of different connections, solder, butt crimps, the butt connectors with the solder, twist and tape.
39:21 And I've tried to keep everything as the same as possible as far as the wire.
39:26 And I've got them sitting outside now to corrode and just see how they all fare and hold up.
39:31 And I did a resistance check between all the connections and actually those butt connectors with the solder inside, a couple of those ended up being, having the least resistance of all the connections.
39:42 While saying that they all were sort of in the same variation, there wasn't a huge discrepancy.
39:49 The only one that had a lot of resistance compared to the rest was the twist and tape.
39:53 So, I just twisted a couple of wires together and taped it.
39:55 That's probably the only one that I'd say, stood out as far as resistance.
40:00 But I did know that those solder butt connectors did have the least resistance of all of them.
40:05 The only thing I don't like about them is they do tend to need quite a bit of heat to get that solder flowing nicely.
40:11 See them used a lot and the solder hasn't actually been heated up enough.
40:15 It doesn't flow nicely.
40:16 It doesn't create that good connection.
40:18 You do really need to get quite a bit of heat in them to get that good low resistance connection.
40:23 So, that's probably, yeah, I'm not, I think there are good quality ones.
40:27 There's definitely bad quality ones as well.
40:29 But if they're used correctly, I don't really see an issue with them.
40:32 I do like that they have that heat shrink around them so, they are protected then.
40:36 But it does sort of play into the whole solder versus crimping.
40:40 If you are getting a good wicking of that solder, there is a good chance that is going to wick up too far and you'll create a stress point further up in the wire.
40:49 So yeah, I think for a good, for a quick connection that you might be, maybe fixing something out in the field, they are good for that.
40:57 But for something long-term, I wouldn't recommend it.
41:00 But yeah, no real definite reasons not to use them.
41:05 Just a preference not to, I guess.
41:07 Next up, I've got Golden Sloth.
41:10 I'm wondering if that's Golden Sloth Racing in South Australia.
41:14 Let me know if it is.
41:16 I know Caleb said even a cheap and cheerful one is good, but is there any recommendations around brands? I'm assuming a Bono set isn't the best way to go and appropriate ha-ha after that.
41:27 So yeah, it's the whole, cheap can be still good, but there is obviously too cheap.
41:36 Find a lot of those cheap crimpers that the actual body itself is really thin.
41:41 I always steer clear of those.
41:43 I've just always found them to have issues.
41:47 As far as actual brands, in Australia, there's Iconic.
41:53 They're really good for sort of having generic tools.
41:59 There's quite a few off the top of my head.
42:02 I mean, the main brands that come to mind for me are things like Delphi and that, but they're, you're actual branded, that will be a bit more expensive.
42:08 But also with those, they can, these days they're not that expensive and you can get a decent set of Delphi crimpers for, you know, a hundred, $200 and they will last you the life of however, long you need them.
42:20 Generally, what I find is the place that you're buying your crimpers, sorry, your terminals and connectors from, even if it's, you know, Repco or probably not, so much Bunnings, they're not as car-oriented, they should have crimpers that are suitable for that terminal.
42:37 It might be their own sort of brand, but it will be a bit of a copy of the higher end brands.
42:43 My only suggestion is do some test crimps, make sure it does work properly.
42:47 If it isn't good, kick up a fuss with the people who sell it because, you know, they got to sell a tool that actually works.
42:53 I recently had, I bought relatively cheap hydraulic crimper for doing cable lugs purely because I needed a step up size that we didn't have already.
43:02 I went for not the cheapest brand, it was sort of mid tier, I guess, but there was only one kind of tool available.
43:08 So, I just went for that one and it turned out the dyes in that tool were absolutely terrible and didn't actually crimp up.
43:17 I did a few tests, I checked it, I saw that it was terrible, took photos, sent it back to the company I bought it from, they were more than happy to return it and give a warranty on that.
43:29 So yeah, testing your tools as well is definitely something you need to do.
43:34 So, I'm just saying here that it is Goldensloth from SA, good to see you, I don't know if you even remember me coming to the SA super clubs back in the day, but yeah, good to see what you're doing with your super, I am still following that.
43:47 Good to finally catch up.
43:49 Yeah, no question, just to follow up.
43:51 Continuing on, I've got Daniel, Daniel-ZN1UT, I'm not sure if there's a way I'm supposed to pronounce that, but yeah.
44:00 Has concentric mil-spec wiring gone too far? That's, ooh, that's controversial.
44:05 Are we gaining anything on vehicles that don't need it or is it mostly for the look and social media? A hundred percent, I see it a lot these days is, I mean, I'm guilty for it as well, concentric twisting things that don't really need to be purely for the look of it and, you know, take some photos and put on social media.
44:23 As far as, you know, if it's gone too far, you are still getting the benefits from it.
44:28 It's one of those situations of, I guess, polishing a turd, like, do you really need to concentric twist your loom? You're not really getting many downsides.
44:38 The only real downsides from concentric twisting is, you know, you're using a bit more wire, spending some more time.
44:43 So, it's sort of weighing that up, I guess.
44:46 As far as, has it gone too far? I'm gonna say no, just because I love a concentric twisted loom.
44:53 I can't say, you know, I'd rather see a concentric twisted loom than not, but yeah, I wouldn't spend the time doing it on a forklift that didn't need it.
45:02 It would be kind of funny to see that though.
45:04 So, maybe I would do that.
45:06 And yeah, as far as, are you gaining anything? You are, but it's just, does that vehicle actually need it? You know, if it's just a daily vehicle and you're trying to save on space and maybe what else are you trying to achieve out of it? Serviceability, that type of thing.
45:24 You are getting those benefits, but at the end of the day, there's probably other parts in that car that are gonna fail a lot sooner.
45:31 So, you don't really need to spend that extra time and money.
45:33 If it comes to something that you're actually paying for, I'd definitely, you know, weigh up whether it is a necessity or not.
45:39 Something me personally, when I do my own cars, I will just do it anyway because I want to, and it's only my own time that I'm wasting and money.
45:47 So yeah, but in full, yeah, it definitely has come to a point where people are doing it just for the social media, that type of thing.
45:56 Continuing on with the questions, we've got Steven Spalding again, 3943.
46:01 Silicon insulation versus traditional wire insulation, which is okay to use in the engine bay? It all comes down to really, the best way to give an answer to that is getting the actual data sheet of the material that you're using and seeing how on paper, what it's supposed to do, how that fares against the environment that you're putting it in.
46:22 With an engine bay, you've obviously got high heat, you've got a lot of moisture, dirt, all that kind of stuff.
46:29 If it's rated to a high temp, then there's no reason not to use it.
46:34 And as far as a silicon versus traditional wire, those kinds of things have their time and a place.
46:42 It might be a situation where the silicon especially, you might be using it when it doesn't need to be that or vice versa.
46:49 But yeah, to give you an actual answer, it's one of those things where it comes down to whether it suits the environment you're putting it in.
46:59 I don't really know how else to answer that one.
47:03 I'd just say, yeah, always grab the data sheet of whatever you're, don't just buy it off the shelf and go use it.
47:08 Look, at a data sheet if you can and see what it is actually rated to.
47:12 That will give you a lot of ideas of whether you should actually be using it in the engine bay or not.
47:17 Next question I got is Beck M-Q1J.
47:21 What is the ideal length for a power distribution module ground cable to chassis? This is one of those, how long is a piece of string or how long is a wire? The shorter, the better, essentially.
47:33 The shorter your wire is, the less resistance of that actual wire.
47:36 So, the less resistance that your electricity has to go through, the better.
47:41 But it is the kind of thing where if your cable is appropriately sized, the length isn't gonna be a problem.
47:48 It's just, as I said at the beginning, if you do have a long length, even if it is for a power distribution module, for an ECU, absolutely anything, if you have no choice, but to run a long ground cable, as long as it's appropriately sized and is making up for any voltage drop type of thing, you're not gonna have any issues.
48:06 So yeah, it's sort of, to answer that question, there is, the ideal length is zero, like as short as possible.
48:15 But also it's, I'd say the ideal length is the appropriate size, the appropriate, what am I trying to say? When your appropriate size cable has no voltage drop, that is the shortest possible distance.
48:34 If you start going longer and you're getting voltage drop, then that's the too long point.
48:39 Anything shorter than that is just bonus.
48:41 So yeah, depending on the size of your cable, the shortest point is whenever, the shortest point you can go is when you're not getting voltage drop, if that makes sense.
48:51 I hope I've worded that properly.
48:53 And next question I've got here, I think this is my last question.
48:56 If you guys got any more, I do have a bit more time.
48:58 So, if you've got any more questions, chuck them in now.
49:02 Ballandirty, that's a great name.
49:04 When doing a LS swap stock ECU with a standalone harness, how in depth should you be in the wiring? Kairos is 71 Camaro.
49:12 When it comes to wiring, you're going pretty deep as it is.
49:19 Going to just kind of assume what you kind of mean here as far as going through the harness and seeing if you need to repair anything, that type of thing.
49:28 What is LS swap stock ECU standalone harness? So, I mean really in a swap into an older 71 Camaro, you don't have to worry about things like dashes and all that kind of stuff.
49:40 Like what I'm trying to say is adapting to dashes in say, if you're putting into a newer car, you're really just going to have your main body electronics integrating into that LS swap and stock ECU.
49:54 So, really I would just be covering, as long as you're covering those basics and then just go over your harness with a, you know, don't have to go too in depth.
50:03 You don't have to rip all your conduit off.
50:05 Look, for problem areas.
50:06 Look, for where maybe some, the conduit around your wiring has maybe melted or abraded.
50:11 If you find something like that, then maybe go a bit in depth, just into that sort of section, see if it's gone through into your wiring or anything like that.
50:18 But as long as it's not a really, really old LS, which it can't really be, but if you're doing sort of older engine looms and older car looms, you do get to a situation where the old insulation starts to get brittle.
50:31 And I often find, if you find just a small section that's gone brutal, chances are it's gone brutal in pretty much the whole loom and it really is better just to start from scratch in that situation.
50:41 You'll find that you might fix a section, but then, you know, a year down the track, the other section goes and you're just chasing your tail.
50:49 So, as far as how in depth you need to go for the wiring, if you're not doing, yeah, aftermarket ECU, anything like that, if everything was working as it, as you took it out of the donor vehicle, just do a bit of a quick glance over, look, for any problem areas, look, for anything broken, that type of thing.
51:04 And that should, yeah, you shouldn't have any future issues.
51:07 Just gonna have a look here, see if there's any other questions.
51:10 I don't think so.
51:11 I think that is it.
51:12 Oh, no, I've got, oh, no, yes.
51:15 Yeah, I've got one more question.
51:16 It's just popped up.
51:18 How many crimps wire extensions is too many? Say I need to extend a wire that I already had crimped, is two crimps okay? To answer the, you know, how many crimps extensions is too many? I'm gonna say one is too many.
51:32 It's just a, it's an idea of, you know, you wanna keep extensions or crimp or joins in your wiring to the minimum possible.
51:42 But of course you get into situations where you actually need it.
51:44 So, you do, it's a necessary evil.
51:47 So, it's more just a situation of the absolute minimum that you need to do.
51:52 If you have a situation where you're repairing a wire and you're, you know, putting in a good piece of wire, you will have to do a crimp or join at both ends.
52:02 So yeah, two crimps in that sort of situation, it is, it's a necessary evil, but it's the kind of thing where way up, whether you can de-pin your connector and replace the entire wire, that way you've only got, you know, the crimp at your terminal at both ends where it's gotta go.
52:17 So yeah, to answer that, how many crimps wire extensions is too many? Any extra crimps or extensions is too many.
52:25 That's the answer to that.
52:26 Keep it to the absolute minimum that you can and, but it is a necessary evil at some situations.
52:33 And we've got one more question.
52:35 What should be shielded? So, when it comes to shielding, you're looking at, when it comes to sensors for your engine, especially your sensitive components are, they, things like your engine speed, cam and crank signal, knock sensors, wheel speed.
52:51 The reason why we need to shield these is the signal that they're transmitting is, it's quite fine and sensitive.
52:59 Like there's not a lot going on there.
53:01 So, if you do get interference from, say magnetic interference from a coil or something like that, or just any added in voltage that shouldn't be there, it really plays havoc on the signal when it gets to your ECU.
53:15 Your ECU will see those little variations and it'll go, what's going on here kind of thing.
53:20 So really, yeah, they're the basics, your knock sensors and speed signals.
53:27 It comes down to, yeah, the sensitive signals.
53:31 Things like your temperature sensors, pressure sensors, analog sensors, they're not as sensitive or as, I mean, safety critical.
53:39 They don't really get affected by noise as much.
53:42 So, you don't have to worry about those when it comes to shielding, but definitely your cam and cranks speed signals, not just because they are sensitive to noise, but also they are critically important to your running of the vehicle.
53:56 And any little bit of interference can cause issues with your ECU trying to work out timing and that type of thing.
54:03 When it comes to other things like CAN bus, they don't need to be shielded.
54:07 They just need to be a twisted pair.
54:09 That mainly comes down to how the CAN bus system works.
54:12 It uses differential voltage.
54:14 So, it actually looks at the voltage on both wires.
54:16 And you just, the whole idea is to keep those wires as close as possible, so that any interference is affecting both wires evenly.
54:24 The situation becomes a problem when those wires are spread out.
54:27 They have a loop in them, that type of thing, and that interference can affect one more than the other or in a different way.
54:34 And then when it's read by the ECU or whatever components reading the CAN bus, that differential voltage is gonna throw things way out of whack and isn't gonna work.
54:44 So, in those situations, doesn't need to be shielded, just needs to be a twisted pair.
54:48 So, there's, yeah, there's different situations.
54:51 Twists, I will just say, you do need to twist sensitive signals as well.
54:56 It helps on top of that shielding, but the shielding is the most important part for those ones.
55:03 I think I've, yeah, I'm just about to get into the end of time.
55:06 So, I'm hoping that has covered enough stuff.
55:10 I really appreciate you guys hanging out and answering those questions.
55:13 It's not answering the questions.
55:15 I answered the questions, but asking questions.
55:17 I do prefer doing that part of the webinars.
55:21 And yeah, join me for some future ones and check out the previous ones.
55:25 Like I mentioned, I do have a few previous webinars in the last few weeks going on things like grounding and especially interference through components of that type of thing.
55:35 I go on that a bit, quite a lot more detail.
55:38 So, thanks for joining us.
55:39 A special thank you to Golden Sloth.
55:41 Great to hear from you.
55:43 And yeah, check out the website with our 2J giveaway and our build section and also join us for the next webinar.
55:50 So, I'll catch you later.
55:51 See ya.