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Practical Reflash Tuning: Step 1: Read ECU

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Step 1: Read ECU


00:00 - The first step of our process is to read the file out of our ECU and save that so we can work with it.
00:06 In this case, WinOLS typically will be used in conjunction with a third party software and hardware interface for the actual reading, writing and check sum correction.
00:17 There are a wide range of these products on the market and for this worked example, we will be using the bFlash product.
00:24 Now while we can perform a read and write for our Mk5 Golf straight through the OBD2 port which means that we can do this from the comfort of the car, I do recommend that we actually start by performing a bench read.
00:39 The reason we do this is that when we perform a bench read using bFlash, it is getting a full read on the entire contents in the ECU.
00:49 On the other hand, when we perform an OBD2 read, we're only actually reading the calibration data out of the ECU, obviously that's the information that we need to make tuning changes but if we do end up in a situation where we have an unresponsive ECU or bricked as it's often referred to, then it can be difficult or impossible to recover that ECU if we've only performed an OBD2 read.
01:15 On the other hand, the bench read reads the entire contents out of the ECU and this should mean that we can recover the ECU if it does become unresponsive.
01:25 Of course the downside of performing the bench read is that in order to do this, we physically need to access the ECU, remove it from the vehicle so that we can actually read it on the bench.
01:37 In the case of the Mk5 Golf this requires us to remove the scuttle panel and the windscreen wipers so we can get access to the ECU.
01:46 It's only a relatively short job though and I do recommend this as opposed to skipping this important step and going straight to the OBD2 read.
01:56 I won't demonstrate the entire process of the bench read within this step but in our bFlash software we want to start by going to our vehicle selection icon up here in the toolbar and click on this.
02:08 There is a list of vehicles we can choose from, we can scroll down to Volkswagen but once you've been using bFlash for a while, we can also switch to the history tab here and that will show us our last use of bFlash, in this case we can see that last time we used it we were doing OBD2 programming but if we scroll back here, we can see that we do have bench programming here for our ECU.
02:34 We could click on this but let's go through the process, we'll go down and we will select Volkswagen and then we need to select the actual controller and in this case we are using the MED 9.1 controller so we'll click on that and then we can choose our read and write method, in this case of course, we want to start with our bench protocol so we can click on that and click OK.
03:01 Next up, we're going to need to attach our bench flashing harness to our bFlash module and this has a range of flying leads which we can then attach to the correct pins on our ECU.
03:14 And in order to find out what those pins are, we can jump back into our bFlash software and we can click on the little help icon here.
03:23 What that will do is give us access to some online information about the particular controller we are working with which we can see has loaded up here, this is the Volkswagen Audi Group Bosch MED 9.1 and we can see here that the header pin out is highlighted and we can see each of the connections we need to make.
03:45 The bench flashing harness is colour coded so it's relatively easy to connect our bench harness to the correct pins.
03:53 I would caution here to make sure that you are very thorough with counting the pin allocation or pin location and making sure that you check and double check that you've got the correct colour connected to the correct pin.
04:08 Obviously if you don't do this correctly, it's potentially going to damage the ECU so always worth double and even triple checking.
04:16 Once you've got the connections set up correctly and everything's connected to our laptop we can also power up the bFlash module, this is one of the advantages of bench flashing as well because one of the most common areas to make a mistake when flashing, reading or writing to the ECU is if the vehicle's battery voltage gets too low.
04:39 And obviously this can be a problem when we are using the OBD2 method.
04:43 When we're doing this on the bench, the bFlash power supply maintains the power supply and controls this so this just takes one variable out of the equation.
04:52 Of course as always we do want to make sure that our laptop is connected to mains power so we don't risk having our laptop go flat as well.
05:01 Once we've got our connections all set up and our bFlash module ready to go, we can close down our help and move back into bFlash itself.
05:10 Now that we're ready to perform our read we can simply select the read icon from our toolbar here and bFlash will prompt us to give the file a name.
05:20 Now again I'm not going to go through this process here, we've done all of the hard work at this point but it is simply a case of naming the file and we can see that I've done that here.
05:29 We're using our normal naming strategy and of course you can do whatever you're comfortable with.
05:34 I've used the registration of the vehicle, followed by the type and make of vehicle and then I've also added stock and bench.
05:42 This just is going to easily make sure that I can recognise this as a full bench read.
05:48 We'll click cancel on that and cancel out of that operation and now we'll go through the process of performing our OBD2 read.
05:55 The reason we're going to do these two reads, as I mentioned we've got that bench read which is a stock read and this is going to be our fallback if anything goes wrong but in terms of our actual tuning process we will be doing our writes via OBD2 for simplicity and speed so we need to have the OBD2 read as well which is the actual file we're going to be working from.
06:17 So to do that, let's head back up to our vehicle selection icon and we can come down to our history and we want to select OBD2 programming.
06:28 Now we're going to click read and the file name will be exactly the same here except of course we are going to call this OBD2 so let's go ahead and enter that.
06:44 Once we've entered our file name we can key the vehicle onto the run position and we can simply click save and the bFlash software will go through the process of the read.
06:59 With our read complete here we can see that the read actually only took 17 seconds which is a bit of a warning flag and we can also see here, if we actually read what the information is telling us that this was all downloaded from a server.
07:13 So this is what's referred to as a virtual read and essentially bFlash has extracted the information on the controller software version and then downloaded a stock file from the internet.
07:25 Now there's pros and cons with this.
07:29 What this means is that we are going to be starting from a stock original file and that's great because it means if we are dealing with a vehicle that has been tuned, it's going to mean that we're ignoring any tune changes which could also mean that we're avoiding some potential errors that have been baked into the tune by a tuner who has previously been there and maybe didn't know what they were doing.
07:53 So that's an advantage.
07:54 The disadvantage of course is that if there has been a tune already on the vehicle, then we are going to lose that information and this potentially could take us back a step in terms of getting back to the power point that the tune was but we'll see how we can progress through that as we go.
08:13 Particularly when we are working with WinOLS and defining the maps inside of the binary file, we really do want to be working from a stock original calibration anyway and this way we're going to be creating versions for our calibrations beyond this.
08:29 We'll always be able to compare those back to the stock file.
08:33 So at this point we've got our file read from the ECU, both via the bench read and OBD2 read methods, we're ready to move on with the next step of our process.

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