Summary

Reading wiring diagrams can be confusing and frustrating if you don't know how to read them. In this webinar, we'll be running through the basic steps to help you understand most automotive wiring diagrams.

00:00 Hey everyone, Caleb here at High Performance Academy.
00:02 Welcome to today's webinar.
00:04 Today we're going to be looking at wiring diagrams.
00:07 They can be pretty confusing sometimes.
00:09 There's quite a bit of information going on.
00:11 You've got modern cars these days with a whole heap of components, a whole heap of wires, and the idea of a wiring diagram, they're trying to lay that out for you nice and neat, but it doesn't always happen.
00:21 So, today we'll go through a few things.
00:23 I'll look over some wire diagrams, we'll do a bit of a diagnostics as if we're looking at the car real world, and how we can use the wiring diagram to actually find a fault in a wiring system.
00:35 So, why do we have wiring diagrams to begin with? Well if you think about how many components are actually going into a wiring system, it's not quite as easy to find a fault as in if it was a mechanical system.
00:46 Something like suspension, you can see quite easily, you know, parts that are supposed to move but don't.
00:52 If something's seized and all that kind of thing, whereas with electrical, it's not that easy to see what's actually happening.
00:58 There's a lot of stuff happening behind the scenes that's invisible to the eye and it gets confusing.
01:02 So, we've got wiring diagrams to help us sort of nut that out.
01:06 It should show us not only where all the wires are going, the colors of wires to expect, but also how the components are interacting with each other.
01:14 And this can be really helpful when we're trying to diagnose why something's not working.
01:19 One of the things that I think people usually go wrong with is looking at a wiring diagram as a whole and looking at all the information, all the lines over each other crisscrossing.
01:30 It can get really confusing and I don't blame you, but I think the best thing you can do is simplify it.
01:36 Look at the component that you're just working on and I'll give you a really good example of that later.
01:40 We're going to go... we're going to look at a wiring diagram for a 2000... it's a 97 to 2004 Hilux.
01:48 I've got a manual off of the Haynes website which is really good.
01:53 Their wiring manuals are really good.
01:55 They've got full workshop manuals which is a great place to find a wiring diagram.
02:00 You can sometimes find your wiring diagrams online just on their own, but I do recommend a full workshop manual.
02:07 You'll get heaps of other information.
02:10 You'll get information on engines, the suspension, all of that, as well as your wiring diagrams.
02:15 And that can be really handy to go back and forth and work things out.
02:19 Haynes is a good paid one.
02:20 There's heaps of different places you can get paid manuals, but you can also do a bit of a search and find your wiring manuals online for free, if you're lucky.
02:29 Sometimes you might accidentally find something that doesn't really work, so be careful.
02:33 You need to sort of cross-reference everything.
02:36 And sometimes you might be unlucky enough that the only wiring diagram you can find is someone's hand drawn and then taken a photo with a 2002 Nokia and uploaded it to the NX5 forums.
02:46 So, that might be all you can get and sometimes you just got to live with that.
02:51 Today the wiring diagram is going to be pretty good.
02:53 I like the way the Haynes manual is laid out.
02:55 It's pretty neat.
02:56 There's not a lot of going on, so it is pretty easy to follow.
02:58 If we, just going over my notes, yeah, we will jump over to the computer and I will show you an example, where, if you think about, maybe one day we are driving along and someone cuts us off, and we got to blast the horn, but the horn does not work, we get this awkward silence; unfortunately, the person that cuts us of has absolutely no idea that they inconvenienced us.
03:24 So, get home and you want to check out your horn, why you horn is not working.
03:27 First thing you generally do, is check your fuse.
03:29 That's just sort of electrical basics.
03:31 If we check our fuse and it's fine, we need to sort of work out where we're going wrong then.
03:37 And the best way to do that is in our wiring diagram.
03:39 So, we can actually work backwards, find out what's wrong and nail it down to just one component rather than replacing a whole different ones while we're guessing.
03:48 And so now if we're looking here on the Haynes manual, this has got everything for quite a few different models.
03:56 It will actually have a section here for chassis electrical system.
04:01 And in there it will have a section for horn and the diagnostics.
04:06 But it doesn't go into the actual wiring diagram.
04:09 It's just sort of a quick check of the components themselves, where they are.
04:13 It does show a good point of testing the horn button itself.
04:17 But we could have issues elsewhere in the system.
04:20 Could be a broken wire.
04:21 Could be a faulty relay.
04:22 So, we will treat it as if we don't have any of this information.
04:26 We're just going to look out the wiring diagram itself.
04:29 If we go over here into the wiring diagram section.
04:31 You see this one.
04:33 For all the Hiluxes, they've spread it out into... I think we've got about 15 different diagrams here.
04:38 So, everything is nicely laid out.
04:40 Everything's not sort of jammed into one page, which is good.
04:43 If we go through we'll see on diagram 11 is our horn.
04:49 So, we're going to just be concentrating on our horn circuit and that's how we're going to simplify things a bit and not get too overwhelmed with how much information is actually there.
04:58 And so we'll go into our horn diagram at the moment which is number 11.
05:03 And also note a lot of the time with simpler circuits like the horn they will share pages with a lot of other circuits.
05:10 So, for in our case we've also got windscreen wipers, four-wheel drive control and the front hub control.
05:16 But at the end of the day all we're worried about is the horn.
05:20 I'll make this full screen so we can see it.
05:22 And straight away looking at this it's pretty nicely laid out.
05:25 We've got color diagrams and stuff so it's not just a black and white mess.
05:29 But we can... or just before we actually go into our example... just go over some of sort of the basics of a wiring diagram and what you might expect.
05:37 So, first usually you'll see your components as just a kind of a block diagram like this.
05:45 Anything from switches, relays, components, control modules.
05:50 There will generally be some sort of a block or in rare cases like this you'll see our horn as an actual picture of a cute little horn.
05:57 Most of the time it is a block though.
05:59 They will be joined together with straight continuous lines which will be simulating our wires and how they connect each component to the other.
06:08 Now, a lot of the time these wires will be crossing over and going all over the place.
06:13 The thing to note is if you look over here we've got lines crossing over and over here we have lines that cross but have a dot.
06:22 The dot is telling us that those wires are actually connected.
06:25 So,, on the left here we've got four different wires.
06:29 Three are vertical, one horizontal.
06:31 They're crossing over each other but there's no dots so we know none of those lines are actually connected in the real world.
06:36 They're all separate wires.
06:38 Over here, with our dots, every single one of these is a wire that is connected.
06:42 In the real world, they might all be connected at the some point and not 3 different points like this, or 4 points, it generally would be just 1 branch point, but for the sake of laying out the diagram neatly, they like to do it like this, which makes it easier to read.
06:57 Sometimes you will see the lines dotted like over to the right here, left sorry, we will go into that a bit later.
07:05 It's a bit of a different detail.
07:06 For now, we will just worry about what we have in the middle here, which is our horn.
07:11 So, looking at our horn circuit, again, looking at it as a whole, the horn circuit really doesn't take up that much room.
07:17 We've got all this going on, and if we want it to be a lot less confusing, all we need to do is look at this section here.
07:26 That's everything to do with the horn circuit.
07:29 Minus one part, which is the fuse, and I will explain that in a second.
07:32 But we can simplify this whole page down to just this rectangle here.
07:36 So, as I said, there is on another page, if I get rid of this, there's another diagram.
07:44 One is our power diagram for just battery, fuses, sort of everywhere that power goes.
07:54 And rather than keeping everything on the same page, they have made it so there's a way of linking each page.
08:02 And here we've got a red 17 at the top.
08:04 So, what this is signifying is that this wire on this page will be joined to another page via that 17.
08:11 You'll be able to look for that.
08:12 Find 17, and that'll tell you that's the same wire.
08:14 And it will tell you here that it is going to the horn fuse in diagram one.
08:19 So, if we look up... if we were to look up in diagram one, you will simply be able to see there's a battery symbol line coming from that to a horn fuse, and then to another 17 like this.
08:31 And that will have a similar text saying to the horn circuit on diagram one.
08:35 So, if you run a couple of So,, going from that, how do we actually test a system using this information? Well, assuming we've done the first step, which is testing the fuse, make sure we've got 12V at the fuse and coming out of the fuse.
08:51 Everything seems good.
08:52 We know that this line here is going to be 12V power.
08:57 It's coming into our system.
08:59 So, from there, the best thing we're going to do is basically just follow everything.
09:03 And the next thing to note is each line will have some sort of identification along the wire that will usually repeat a few times.
09:11 It'll be generally a letter of some sort.
09:14 And this is to tell us what colour the wires is.
09:16 Now, a lot of the time, this might not be intuitive.
09:21 Toyota, sometimes I think one of their lettering is S for grey, which makes a lot of sense.
09:27 But you will have on your diagram some sort of legend somewhere.
09:31 On our example, if we look... Right down the bottom, to the bottom left, we'll see...
09:36 I'll try and zoom in on that for you.
09:38 Down here, we have... That's too much.
09:40 The legend.
09:41 And this will clearly tell us what is what.
09:44 Now, our wire was a LW, which is simply telling us we've got blue and white.
09:54 Having two identifiers, that's telling us there's a main colour, which will be blue, our first letter.
09:59 Second colour, white, that'll be our trace.
10:02 And... The majority of the time, this is how it will be.
10:04 Sometimes it might be separated with a slash.
10:07 Generally, if there's two identifiers, it'll be the main colour and an identifying stripe.
10:13 Sometimes they might use separate letters, like for brown, they might just use the first two letters.
10:21 And the way they'll do this is generally a capital B with a lowercase r, and any uppercase letters after that will be your stripe colour.
10:29 So, that lets us then identify in the real world... What colour wires are doing what.
10:34 So, we know now there is a blue with white trace wire that should have 12V coming all the way down here.
10:40 If we continue following it...
10:42 We'll find in the centre here, our horn relay.
10:45 Now, the horn relay is probably going to be the best point in this system to test different parts and get all of our information.
10:53 So, the next step would be to find this horn relay on the car.
10:57 In the last section that I showed you, where it was showing how to diagnose the car, it did actually tell you where to find the horn relay.
11:03 Sometimes you're not that lucky and you have to do a bit of a search, but you'll usually have some sort of diagram on the car.
11:08 You can find where the relay is.
11:11 Relay is a really good point for testing because we can easily take the relay out.
11:16 And that then gives us some good points.
11:18 The pins are good sections where we can actually test voltage, test for ground, without having the whole circuit connected and possibly causing other issues.
11:27 If we have, maybe for example, a short circuit somewhere.
11:29 If we take that relay out, it can prevent us from continuing to short circuit and wasting fuses.
11:34 So, we'll say we have found that horn relay.
11:38 And our image here of the horn relay we've actually got shows us how are the internals of the relay itself.
11:45 So, we've got the switching and the coil.
11:47 Now, most of you are probably used to 4 and 5 pin relays.
11:52 They have your common sides of the switch in and out.
11:56 And then the coil positive and negative sides.
12:00 This one is only a 3 pin, which you can tell by the identifying numbers and pins in each corner in the bottom.
12:08 So, this is telling us it's a 3 pin relay.
12:10 And if we were to actually find the relay, these numbers should correspond to the relay itself and be imprinted on the relay somewhere.
12:18 Generally,, they'll also show a symbol sort of similar to this or identical on the relay itself.
12:25 And looking at this.
12:26 We can see it's only a 3 pin.
12:28 Because on pin 2 we can see it is sharing via a small connection there.
12:34 Our dotted line on the transition.
12:37 That it's sharing 12 volt to both one side of the switch and to one side of the coil.
12:42 So, now if we go to our relay in real world, we know we should expect on this pin 2 to have 12 volt.
12:48 So, we can get our multimeter, find a good earth on the engine somewhere or anywhere on the chassis.
12:53 And test for 12 volt at pin 2.
12:56 And let's say we have got 12 volt.
12:59 We know that's all good.
13:00 We can continue testing.
13:01 Or maybe in our case we haven't got 12 volt.
13:03 In that situation, we've had 12 volt after our fuse but no 12 volt at our relay.
13:08 That would tell us somewhere along this line we've actually got a fault, an open circuit.
13:13 And we can trace that line, follow the wire through the car and find our fault.
13:18 But to continue on our example, we'll say that we've got 12 volt on the pin 2.
13:24 So, we have 12 volt to one side of our switch.
13:26 And one side of our coil.
13:28 And we know for relays we need power and earth on our coil to get it to activate.
13:34 And pull that switch contact down.
13:36 So, in some cases you might need to test and actually see on the wiring diagram which side is positive, which side is negative.
13:45 We know straight away that the left side here is our positive because it shares with our positive input from the fuse.
13:52 Knowing that, we know on the other side here needs to be an earth.
13:55 So, we can go to pin 1 here.
13:59 And we can check there for an earth.
14:01 We need basically, if we have a multimeter on pin 2, across to pin 1, we should expect 12 volt there.
14:10 We know though that this is being a horn, it's got to be switched in some way.
14:14 And if we look down the bottom here, we have our horn switch.
14:18 Which we all know as the big button in front of us when we're driving along.
14:22 So, what we should expect is when our horn switch is depressed.
14:25 We should get earth on this pin and give us 12 volt across those two pins.
14:31 Now,, if we're having some issues there, we can...
14:35 One of two things, we can go... we can test at the relay or we can test at the horn switch itself.
14:40 End of the day, testing both is going to just confirm things and make it obvious what the answer is.
14:47 So, we can test here if we get earth as we're pushing the switch.
14:51 If we are getting earth, we know that whole section is good.
14:54 If we're not, however, we can trace back even further.
14:57 Following this GR, which I believe is green-red.
15:01 And we can go all the way to the steering wheel and we'll find the switch, which is our horn pad.
15:06 And you'll notice the symbol at the bottom here, which is a pretty common symbol used for a ground or chassis ground.
15:13 This is simply linking everything labeled with that symbol as a ground.
15:18 So, on the left here, you'll notice there's another one.
15:20 I didn't mean to cross it out.
15:21 Another one over here.
15:23 Another one up here.
15:24 And our horn switch, obviously.
15:26 This is just saying there'll be another one over by a battery on diagram one.
15:31 And it's saying they're all linked together.
15:33 So, that's all chassis ground.
15:35 Sometimes these will be in a common spot and it will actually tell you where that earth is.
15:41 If we look down at the bottom right here, there are two small grounds in the corner.
15:47 It actually tells you that they're the right-hand A-pillar and left-hand A -pillar.
15:51 This makes it really handy for finding those grounds and confirming that they're actually connected.
15:56 Going back to our horn though, you'll notice on our horn switch, there isn't a wire necessarily coming off the horn switch itself.
16:05 So, there's no real connection here.
16:09 There's no wire.
16:10 It's purely... Sorry for zooming out again.
16:13 It's actually a part of the horn switch itself.
16:15 So, as you may know, if you've pulled a horn button apart before, the horn itself is a single wire.
16:23 And it makes contact through the switch to the steering wheel itself, to the chassis ground.
16:29 So, there's no second wire after this.
16:31 It is directly to chassis ground.
16:34 And we have nothing really further to test there.
16:36 We can, if say we test on one side of the horn switch and we're not getting a good ground, we may have bad contacts.
16:43 There may be a poor ground and connection in the horn switch itself, which we can diagnose.
16:49 Not usually the problem.
16:50 So, we'll continue on.
16:52 And we'll say that we've tested pin 1 and we are getting a really good ground there when we're pushing the switch.
16:59 Having said that, if we've got 12 volt on our pin 2 and pin 1 has our ground, we should expect this coil to energize and pull our contact close.
17:10 Now, we could have tested this earlier simply by listening to the relay.
17:14 When it's plugged in, we should hear an audible click as the horn switch pressed.
17:19 But for this sake, we want to actually test every component separately.
17:22 From here though, once we've got confirmed the 12 volt nerf, we can put the relay back in, hit the switch, and we should hear an audible click and know that that is working.
17:32 Having said that as well though, just because the coil is working and pulling the contacts closed, there may be a fault internally causing the switch not to function properly or not to close completely.
17:43 So, it does help to continue testing.
17:46 From this point, we can move up following the line.
17:50 It'll actually go to the horn itself.
17:51 So, we've got our picture here of the horn.
17:54 And this is another place where people can sometimes get stuck.
17:58 The 12 volt positive side of the horn from the relay is actually labeled as a B or black wire.
18:05 So, going to the horn, we would see a black wire coming out and going to our relay or may not even see it going to a relay.
18:10 Some people wouldn't be blamed if you were to think that that was ground and not 12 volt positive.
18:18 So, without a wiring diagram, someone might look at that circuit and think, okay, cool, I need a ground there, put ground to it, cause a short circuit and just cause more problems, more headaches and go chasing the proverbial goose down whatever hole.
18:32 So, using a wire diagram, we're already saving a lot of time by knowing exactly what wire is what, what the color is and what we should expect there.
18:41 So, going to our example again, when we have our horn relay in, our horn button pressed, we should be getting 12 volt at this point in the horn.
18:50 We can test that easily with a multimeter on the car.
18:53 If we're not getting our 12 volt, we know then that there is a problem between our horn and the horn relay.
18:59 In this sort of situation, you can easily check with continuity.
19:03 Just check from the horn itself.
19:05 It is kind of hard to test the relay if it is putting power out because you need the relay connected.
19:11 You can't test the pin with the relay connected.
19:14 You might have to be a back probe.
19:16 So,metimes you can get access, most of the time you can't.
19:19 So, it is generally easier just to check continuity between these points with the relay disconnected.
19:25 So, say we've checked all that.
19:26 Everything is still going well.
19:28 We've got 12 volt to our horn, but we still don't have any beep beep.
19:32 So, what next? Looking at the diagram, we know we've got 12 volt.
19:37 We need earth.
19:38 So, on the other side, we've got a white black wire and we can see that they are going to two earthing points.
19:45 And this is a point that I wanted to show.
19:48 It has a note here.
19:49 Except 1KZTE.
19:53 A lot of wiring diagrams will cover a broad range in a specific model.
20:00 The Hilux in particular in Australia, we came out with a lot of different engines.
20:06 In the example case, was my Hilux, I had a 3RZ.
20:12 So, looking at this diagram, any Hilux that didn't have a 1KZTE should have this extra output.
20:19 Whereas the Hilux that had the 1KZTE won't actually have that earth there.
20:24 They only have a single earth at the top.
20:26 Lots of different points like this throughout wiring diagrams.
20:29 So, you've really got to be sure of the information of your vehicle and what you're looking at.
20:34 So, going through, we've found our earth.
20:37 We know if we trace that wire, we should trace it to a good chassis earth.
20:41 If we're not testing a good earth at the horn, we know we'll probably have a dirty ground.
20:46 It's not tightened up.
20:47 Someone hasn't done it up.
20:48 And we can get all that fixed and get the horn working.
20:51 Or we'll see that there is an earth there.
20:53 We'll see there's 12V.
20:55 From that point, we can confirm the horn is the faulty item.
20:58 So, we've just gone through this whole wiring diagram here.
21:01 And used it to really simplify our circuit.
21:05 Take it one step at a time rather than looking at it as a whole.
21:08 Looked at each wire.
21:09 Thought about what we should expect to see there voltage-wise.
21:12 And that's allowed us to test each component.
21:15 And at the end of the day, that's been really helpful.
21:17 Because rather than just buying parts and saying, hey, the horn's not working, we'll replace the horn.
21:23 We know for sure what component isn't actually working.
21:28 So, that gives you a good example.
21:32 Probably, what should I go into next? The next best thing to talk about is actually some other components of the wiring diagram.
21:39 Because there is a lot going on here.
21:40 If we look at it a bit more broader.
21:42 We've got, as I said about other models in the same diagram.
21:47 You'll see here.
21:48 The wiper circuit in the left here.
21:50 We've got two of almost an identical diagram.
21:54 But in the right-hand corner, we can see it says models to July 1999.
21:59 Or models from August 1999.
22:01 So, we've really got to be sure of what model we're looking at the year.
22:04 Because there can be some little differences.
22:06 Where for this, I think it's literally just how the switch sort of connects internally.
22:11 But to test properly, we really need to confirm those kinds of information.
22:17 I'll just take a second to remind you that this will be a recorded webinar.
22:22 And it will be up online later.
22:24 So, if you haven't got the chance to go through it all now.
22:26 That's fine.
22:27 And you can go through it later.
22:29 Also, if you've got any questions.
22:31 Chuck them into the chat.
22:32 And I'll get to them at the end.
22:34 And before that though.
22:36 We're going to go into... Let's check my notes.
22:39 Yep.
22:40 So, we've gone through a good example of how you'd use a diagram.
22:45 The main reason for doing this.
22:47 Is so that we don't end up replacing multiple different parts.
22:50 We can really narrow it down to...
22:52 Hopefully just one bad component.
22:55 If you own a Honda.
22:56 It might be multiple bad components.
22:58 But you're not wasting time.
22:59 You're not wasting money.
23:00 And you're really getting to the heart of the problem.
23:04 Again.
23:05 If you have any questions about any of this.
23:07 If you see anything on here that you want me to explain further.
23:09 Chuck it in the chat.
23:10 And we'll have another look at it a bit later.
23:13 We'll go back to the computer.
23:16 And I'll go over some more bits and pieces of this.
23:20 So, I was talking about over here.
23:22 The switches.
23:23 And how they might differ from model to model.
23:26 If we have a look at this.
23:28 What we'll see.
23:30 This is a function diagram.
23:33 It'll tell us how that switch actually works.
23:36 So, we can see on the left here.
23:38 We've got.
23:39 These are the switching positions.
23:40 Off.
23:41 Intermittent.
23:41 Low.
23:42 High.
23:42 And washer.
23:43 Our columns will then tell us.
23:46 Each column is connected to a pin.
23:49 Which are numbered here.
23:50 So, we can see this is pin 11.
23:53 Or here is pin 17.
23:56 Basically, that is telling us.
23:58 It's representing a pin in the connector itself.
24:01 Which we can see over here.
24:02 Pin 11 would be here.
24:04 And pin 17 over here.
24:07 So, with this.
24:08 Using the diagram here.
24:10 We'd be able to tell that.
24:12 When the switch is in the higher position.
24:15 We'd have a connection along here.
24:17 Which is connecting pin 11 and pin 17.
24:20 So, we can check this on the car.
24:21 Or even off the car with the continuity testing.
24:23 We should get continuity between these two pins.
24:26 On that higher position.
24:28 It'll tell us if the switch is working properly.
24:30 If it isn't.
24:31 And again we can diagnose the actual faulty part.
24:34 I'll go into as well.
24:36 Looking at connectors.
24:38 Can be a little bit confusing.
24:41 It's generally.
24:42 Which side of the connector you're looking at.
24:44 Can be the confusing part.
24:45 Because looking at this.
24:46 We know vertically.
24:48 This is representing the locking pin.
24:50 The locking tabs on top.
24:52 So, we know sort of which way that is orientated.
24:55 Excuse me.
24:56 But we may not know.
24:57 Which way the connector is actually flipped horizontally.
25:00 We could be looking from the front.
25:01 We could be looking from the back.
25:03 Best thing to do.
25:04 Is to actually get the connector itself.
25:08 If you have it with wires.
25:09 We can see what wires we've got.
25:11 And actually correspond that to our diagram.
25:14 And that should give us a good idea.
25:16 So, for example.
25:17 If we were to look at pin 11.
25:19 We can see it is labeled with an X.
25:21 Which looking at our diagram.
25:23 Is a light green.
25:24 And then also looking at pin 17.
25:27 We've got blue, red.
25:29 Blue with a red trace.
25:31 So, going to our connector.
25:32 We can see those pins are here in the corner.
25:34 There's second from the bottom.
25:36 On the left.
25:37 And second in the bottom.
25:38 On the right.
25:39 So, looking at our connector in real life.
25:43 We should see those same colors in those pins.
25:46 And depending on which way they are.
25:48 Will tell us which way we're looking at that connector.
25:50 And that's another good note.
25:53 Sometimes our wiring diagrams may not match up color wise.
25:56 It is a problem with some different manufacturers.
26:00 That sort of thing.
26:00 Things might change.
26:02 And you might be unlucky that way.
26:03 It is very hard to find good wiring diagrams sometimes.
26:07 But hopefully in your case you've found the right one.
26:11 And your wiring colors match up.
26:12 Sometimes it can help to just have a bit of a look around.
26:15 And really find a few different ones.
26:17 Find the best one.
26:18 In this case a paid one usually will have the best answers.
26:23 Another point to look at here.
26:25 As I said components will generally be a block.
26:29 Or just a square rectangle symbol.
26:33 This one here has this wavy line.
26:35 That is telling us that this is part of a bigger component.
26:40 So, if we read here it says here that it is the wiper switch.
26:42 Which is part of the combination switch.
26:45 So, all this is telling us is that there's actually a lot more going on with this part.
26:49 We can see the connector has quite a few pins.
26:51 Which aren't represented here.
26:52 We've only got a few of them.
26:54 The rest of these pins will be for a different switch.
26:57 But really at the end of the day like I said we want to simplify things.
27:00 So, this is doing that for us already.
27:02 Rather than showing us all these components.
27:04 That it is relevant for.
27:07 It's just showing us the one circuit that we want to look at which here would be the wiper switch.
27:11 And that makes things a lot easier to read.
27:14 It brings me to the dotted lines.
27:16 Which I mentioned earlier.
27:18 This is again to do with our different models.
27:21 The July 1999 and August 1999.
27:25 Basically, if it has a dotted line.
27:27 Interrupted line.
27:28 Something like that.
27:29 Generally, means it's saying that it could be present in one model and not the other.
27:36 If we look at the top here, we've got our constant line in, which then splits to the left, which is constant.
27:42 That tells us that it is going to be in every model.
27:45 Being a constant line.
27:46 It is not going to be split up in any other model.
27:49 But each model will have a different switch.
27:52 And it will only go to one of these two lines.
27:54 Depending on your model.
27:56 This can be where things get a little bit confusing.
27:58 But again having the right information.
28:00 You'll be able to find just the right component for you.
28:02 And what part is actually relevant.
28:04 For you.
28:04 In our case.
28:06 Say we're looking at my ute, which was a 2002.
28:08 We'd only look at this right hand side.
28:10 And we completely ignore the left.
28:11 And looking down the bottom as well where these wires come out.
28:15 Again, they're only going to be coming from one of these two switches.
28:19 So, in our case it will be coming from the right.
28:21 And then into our wiper motor itself.
28:23 And wouldn't be making a connection to the non-existent wiper switch.
28:27 From a past vehicle.
28:30 What else did I have here? That was really... Yeah, all talking about this.
28:34 Again, things can really change between manufacturers.
28:39 It pays sometimes just to have a quick look through your wiring diagrams.
28:43 Really get a feel for how that particular manufacturer.
28:46 Even just the manufacturer of that diagram itself.
28:48 The people who printed it.
28:50 They all do something a little bit differently.
28:52 How they lay things out.
28:53 Maybe even how they represent colors.
28:55 So, get used to your manufacturer.
28:59 Personal preference Toyota.
29:01 They do things really well.
29:02 Sometimes.
29:03 But from that...
29:06 Really this should give you a pretty good idea of what goes on in a wiring diagram.
29:11 How you can use it to help you find a fault.
29:15 Diagnose it.
29:16 Get to the bottom of it.
29:17 Without just throwing parts.
29:19 Hopefully gives you some good idea of a wiring diagram.
29:23 Sometimes they're not quite this well laid out.
29:25 I do actually have an example here of...
29:30 Not quite... I wouldn't say it's badly laid out.
29:33 But I've got a wiring diagram from an R32 Skyline.
29:38 The thing is.
29:39 Everything is sort of all jumbled up onto one page.
29:42 And if I get the overhead here.
29:45 We'll be able to see.
29:47 If you try to print it out on one page.
29:49 There's not enough room for it.
29:51 And things just get blurry and messy.
29:54 And it's really hard to really see what's going on.
29:57 My best advice for this is again.
30:00 Break things down to just the components that you're looking for.
30:03 If you look around this wiring diagram.
30:05 It might be a bit hard to see on screen.
30:06 But the components are all around the outside.
30:09 Just find what you're looking for.
30:10 For example.
30:11 Here is our break level switch.
30:14 We could just be looking at that circuit.
30:16 Keep your eyes just here.
30:17 Only look at those points.
30:19 And it'll make things a lot easier.
30:21 Another point to look at with wiring diagrams.
30:24 This one is actually across two separate pages.
30:28 In this case.
30:30 The lines should usually line up between the two pages.
30:34 This can be a bit difficult sometimes if you're looking at it online.
30:37 And it can help to actually print it off.
30:39 Just for getting sort of that reference of where things are going.
30:41 How they mate up.
30:44 In this case.
30:45 I would still look at it on the computer.
30:46 You just have to really get your head around where these wires are going.
30:49 Keeping in mind that it is going to a separate diagram.
30:52 But they are connected.
30:53 It should be pretty well laid out to make this easier.
30:57 Another thing with these diagrams, you sometimes get a harness layout which is this here.
31:05 These can be really handy.
31:06 They won't so much show you the circuit.
31:09 But how the loom is actually laid out.
31:11 Again, that can be really handy just for finding components.
31:14 For example.
31:15 If we were to be looking for that break level switch.
31:18 That I pointed out on the wiring diagram.
31:21 We can go through the list here.
31:23 And it is right here at the start.
31:25 We can see it is in loom A.
31:28 I think that is actually saying in section A.
31:30 Engine loom H.
31:32 Which is labelled here.
31:33 Pointing at this loom here.
31:35 Now, these are all separated by colours.
31:37 To make it a bit easier to look at.
31:39 So, everything red in this section.
31:41 Is just that single loom.
31:43 It is labelled as number 3.
31:45 Which you probably can't see on the camera.
31:48 But that is labelled up here in the top.
31:50 So, we know that connector is going to be going to our break level switch.
31:53 We can then go back to our wiring diagram.
31:56 And we know that.
31:58 That point there is connected to that point in the car.
32:00 And we can actually do our testing.
32:02 If you have got any more questions.
32:03 We are going to be getting to the end of the webinar soon.
32:05 So, hit them up on the chat.
32:07 And I will try and answer them to the best of my ability.
32:11 Going over a bit more what wiring diagrams are good for.
32:16 Not even just diagnosing.
32:18 But say you want to add in something to your car.
32:21 You for example have a Hilux like we do here.
32:25 If we have a look at our diagrams again.
32:28 Engine diagram is really good.
32:29 The engine ECU sorry.
32:31 It will show us every component that is connected to that wiring diagram.
32:35 And if we for example wanted to wire in a new ECU.
32:37 An aftermarket Emtron KV16 into a Hilux.
32:41 Because that is what we all want to do.
32:42 This will show us all the different components.
32:45 What pin they go to on the ECU.
32:47 That makes it a lot easier for us to then wire in.
32:50 We don't have to actually pull the loom out.
32:52 And continuity test each thing to find out where it goes.
32:56 We can make a patch harness.
32:57 We can cut the connector off.
32:59 Wire it straight into our ECU.
33:00 But it really gives us a good starting plan.
33:03 And somewhere to go from.
33:04 And you will see on this diagram.
33:05 Again, it has got our red numbers.
33:10 Which will correspond to another diagram.
33:14 So, there may be a bit of flicking back and forth.
33:16 But all in all it gives us some really good information.
33:18 Like each separate injector.
33:20 It will show us where that power is coming from.
33:22 It will then show us what pins on the ECU actually wire up to.
33:27 To each injector.
33:28 Which is critical information when you are using a standard loom.
33:31 And you want to wire it up to a new ECU.
33:33 And so really that breaks it down.
33:36 Like I said there are some diagrams that are hard to read.
33:39 Some are a bit easier.
33:40 At the end of the day it really comes down to what you can find.
33:44 Just having a good search is the best thing you can do.
33:47 I will have a look now at what questions we got.
33:49 And hopefully I will be able to answer some of them.
33:52 Okay we have here.
33:55 Jack Schofield.
33:56 Do you have any tips for passing dense wire diagrams that span multiple pages? Say in a service manual.
34:03 Find out if having to print them out, tape together and use a highlighter tracks certain circuits.
34:07 Yeah, I completely understand this.
34:09 This is like what I was going over with our diagrams over here.
34:13 My tips...
34:16 I like to print it off as well.
34:18 I get that.
34:19 I like to print it off.
34:19 Highlight each diagram.
34:21 Each circuit where it goes.
34:22 Really sometimes you can't get away with not printing them off.
34:26 But for something that is as intricate as what I showed you on the down camera.
34:31 You can if you find it on the computer first.
34:34 Crop it to just that section.
34:35 To just the wires that you are looking for.
34:37 Blow it up a bit.
34:38 And then print it off so it is a bit clearer.
34:40 Don't have all the other information that you have to deal with.
34:43 That really is the only tip I can give you.
34:47 Unfortunately sometimes printing it off really does give you that better layout.
34:52 And you are not sort of mucking around with the computer.
34:54 And losing your spot in a PDF or something.
34:58 We have here another question.
35:01 From...
35:03 Username is Havizron.
35:05 How can we reliably identify ground reference points in a wiring diagram? And what is the best way to check for ground loops or voltage offsets when diagnosing signal integrity issues? Beginning with the ground reference points.
35:18 As I was showing.
35:19 If we have a look on the diagrams again.
35:21 I will go back to our...
35:23 Windscreen wipers.
35:25 So, I talked about how they use the same symbol as their common reference for ground.
35:32 Sometimes these might be going to the same point.
35:34 Sometimes they are separate points.
35:36 Like they explain here.
35:38 Right hand A pillar.
35:39 Left hand A pillar.
35:40 They will all go back to... I will show the power supply charging diagnostic.
35:46 This will show us a diagram of all the power supplies.
35:51 And we can see here in the corner.
35:52 If I blow this up a little bit.
35:55 Too much.
35:56 The battery itself has one of these symbols connected to it.
36:00 And with most electrical diagrams.
36:04 These symbols are used as a common reference point.
36:07 So, we know that every time we see this symbol.
36:10 These wires are all connected together.
36:12 And at the end of the day.
36:13 They are all connected back to the negative of the battery.
36:16 As far as the rest of the question.
36:18 Which I go back and have a look at.
36:20 Okay.
36:22 Checking for ground loops or voltage offsets.
36:25 When diagnosing signal integrity issues.
36:28 Honestly at the moment.
36:30 I couldn't really give you a good tip for that.
36:32 My head is in diagrams.
36:34 That goes into electrical issues a lot more.
36:37 We might be able to do another video on that later.
36:41 If you need some support right now.
36:44 My best tip.
36:45 Go to the...
36:47 We got a support email that you can email.
36:49 And we will be able to get back to you as soon as possible.
36:51 Or even jump on the forums.
36:52 There is a lot of great people on there.
36:53 Including ourselves.
36:54 You can get some good information off that.
36:57 Another question we got here.
37:00 The name is Anujer00.
37:04 Sorry if I am butchering your names.
37:07 What do you recommend a diagram to have to be considered usable? At the end of the day.
37:13 The best and most usable diagram.
37:15 Is going to be what matches your vehicle.
37:17 You really can't go wrong with.
37:19 Cross referencing to your vehicle.
37:22 Have a look at your connectors.
37:24 See if your colours match up.
37:28 If the connectors match up.
37:30 Have a look at your connectors themselves.
37:32 The pin outs.
37:34 Sometimes the pin out will actually show you.
37:37 If there is a wire there.
37:38 Or if it is just a blank hole.
37:40 Or a blank terminal.
37:41 If you correspond that over to the connectors in your car.
37:44 That will give you a good idea.
37:45 If you are actually working with the right one.
37:47 This can get pretty annoying sometimes.
37:49 I have had in the past.
37:51 You will get the wiring diagram.
37:53 Which is supposed to be for your model car.
37:55 But in actual fact.
37:56 There has been updates to the wiring diagram later on.
37:59 And you have to sift through heaps of different wiring diagrams.
38:02 Unfortunately it is a pain of electrical.
38:06 At the end of the day though.
38:07 Once you have found that wiring diagram for your car.
38:10 It is invaluable.
38:11 It helps you a lot.
38:12 And when those wiring colours match up.
38:14 It is a good feeling.
38:16 As far as questions.
38:17 That seems like everything we have got in our Q&A.
38:20 Hopefully that has given you some good insight.
38:22 Into reading electrical wiring diagrams.
38:25 How they can be helpful.
38:26 They definitely are invaluable.
38:28 And they definitely help when fault finding.
38:30 Saves you that time of just throwing parts.
38:33 And wasting money and time.
38:35 If you are not watching this live, and you have more questions, email them to us.
38:40 The support or jump on the forums and chuck your question on there.
38:44 And we will try and get to it.
38:45 Other than that.
38:46 I hope you have enjoyed this.
38:48 And look forward to seeing you next week.