Inexpensive Opensource Flashing(Read is 100% working)
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I still need to take it for a drive though, just to make sure it doesn't come back.
The nice thing about flashing the calibration alone is that a bad calibration flash is relatively easy to fix - no special tools or soldering. But fixing a bad OS flash requires about $70 for the Background Debug Mode tool, and you'd have to solder several wires to the PCM's circuit board.
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From a 2003 Chevy truck. Here are instructions to troubleshoot and code definition. Problem is likely battery/cables, fuse, wiring. Step one is checking your fuses.
1. Clear the DTC. Start and run the engine.
2. If the DTC P1518 returns immediately, check for battery voltage to the Pink wire on the 16-cavity Clear colored connector at the Throttle Actuator Control (TAC) Module. Check the ground on the top left at the bellhousing to block bolts. Verify the Orange/Black wire between pin 12 on the Clear connector at the TAC module to the Blue connector pin 14 of the Powertrain Control Module (PCM). Verify the Dark Blue/White wire at pin 13 on the Clear connector at the TAC module to the Blue connector pin 15 at the PCM.
3. If the DTC does not reset,verify connectors for pin fitment. Wiggle and pull on the harness in an attempt to recreate the failure.
P1518 Throttle Actuator Control Module Serial Data Malfunction =leftPossible CausesSetting Conditions
1. Clear the DTC. Start and run the engine.
2. If the DTC P1518 returns immediately, check for battery voltage to the Pink wire on the 16-cavity Clear colored connector at the Throttle Actuator Control (TAC) Module. Check the ground on the top left at the bellhousing to block bolts. Verify the Orange/Black wire between pin 12 on the Clear connector at the TAC module to the Blue connector pin 14 of the Powertrain Control Module (PCM). Verify the Dark Blue/White wire at pin 13 on the Clear connector at the TAC module to the Blue connector pin 15 at the PCM.
3. If the DTC does not reset,verify connectors for pin fitment. Wiggle and pull on the harness in an attempt to recreate the failure.
P1518 Throttle Actuator Control Module Serial Data Malfunction =leftPossible CausesSetting Conditions
- DTC P1518 sets if the battery voltage is low. If the customer's concern is slow cranking or no crank due to low battery voltage, ignore the DTC P1518. Clear codes that set due to low voltage.
- DTC P1518 also sets when there is a short to B+ on the TAC module ground circuit. Inspect the Brake and Cruise fuses first.
I just tried to set up a p59 DBW setup on my bench harness for some testing. I didn't pull any codes but it was not working correctly until I had the TAC module and PCM switched 12v input get power at the exact same time. I think if they don't get power at similar times they won't sync up and it'll go into an error mode. So if the TAC module is powered on the whole time and then the PCM gets flashed and reboots or whatever it does it seems likely that could be the issue? I'm not sure how to remedy it other than a few key cycles to get it to clear the error if that's the case?
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"A few key cycles" seems to be what fixed it in my car, but I think the app can send a message to the PCM to clear the code. We're sending a couple messages already, but I'm going to make some changes to one of them and see what happens. I think we just have the wrong "priority" byte at the start of the message.
"A few key cycles" seems to be what fixed it in my car, but I think the app can send a message to the PCM to clear the code. We're sending a couple messages already, but I'm going to make some changes to one of them and see what happens. I think we just have the wrong "priority" byte at the start of the message.
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Teching In
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P1518 is set when communication is lost between PCM and this module. GM notes that this can occur during reprogramming.
To resolve this, you need to ensure that *any other* DTC's are cleared, then clear this.
Also, I assume you are attempting to clear from the ECU? You also need to talk directly to the TAC module and clear any DTC's on that end. (e.g. you need to clear TAC module, then ECU for this to go away; otherwise, it will go away on its own after a few drive cycles.)
If you threw a Tech II on this, you'll see that the code is not current, etc.
P.S. Don't mind my 4 posts since the year 2004.... I originally posted on this forum back when Magnus was trying to do Open Source and was kicked when warning people he was going to screw them..... Now I'm back, again, but hopefully this one really stays open source. What's old is new again.
To resolve this, you need to ensure that *any other* DTC's are cleared, then clear this.
Also, I assume you are attempting to clear from the ECU? You also need to talk directly to the TAC module and clear any DTC's on that end. (e.g. you need to clear TAC module, then ECU for this to go away; otherwise, it will go away on its own after a few drive cycles.)
If you threw a Tech II on this, you'll see that the code is not current, etc.
P.S. Don't mind my 4 posts since the year 2004.... I originally posted on this forum back when Magnus was trying to do Open Source and was kicked when warning people he was going to screw them..... Now I'm back, again, but hopefully this one really stays open source. What's old is new again.
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P1518 is set when communication is lost between PCM and this module. GM notes that this can occur during reprogramming.
To resolve this, you need to ensure that *any other* DTC's are cleared, then clear this.
Also, I assume you are attempting to clear from the ECU? You also need to talk directly to the TAC module and clear any DTC's on that end. (e.g. you need to clear TAC module, then ECU for this to go away; otherwise, it will go away on its own after a few drive cycles.)
If you threw a Tech II on this, you'll see that the code is not current, etc.
P.S. Don't mind my 4 posts since the year 2004.... I originally posted on this forum back when Magnus was trying to do Open Source and was kicked when warning people he was going to screw them..... Now I'm back, again, but hopefully this one really stays open source. What's old is new again.
To resolve this, you need to ensure that *any other* DTC's are cleared, then clear this.
Also, I assume you are attempting to clear from the ECU? You also need to talk directly to the TAC module and clear any DTC's on that end. (e.g. you need to clear TAC module, then ECU for this to go away; otherwise, it will go away on its own after a few drive cycles.)
If you threw a Tech II on this, you'll see that the code is not current, etc.
P.S. Don't mind my 4 posts since the year 2004.... I originally posted on this forum back when Magnus was trying to do Open Source and was kicked when warning people he was going to screw them..... Now I'm back, again, but hopefully this one really stays open source. What's old is new again.
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P1518 is set when communication is lost between PCM and this module. GM notes that this can occur during reprogramming.
To resolve this, you need to ensure that *any other* DTC's are cleared, then clear this.
Also, I assume you are attempting to clear from the ECU? You also need to talk directly to the TAC module and clear any DTC's on that end. (e.g. you need to clear TAC module, then ECU for this to go away; otherwise, it will go away on its own after a few drive cycles.)
If you threw a Tech II on this, you'll see that the code is not current, etc.
P.S. Don't mind my 4 posts since the year 2004.... I originally posted on this forum back when Magnus was trying to do Open Source and was kicked when warning people he was going to screw them..... Now I'm back, again, but hopefully this one really stays open source. What's old is new again.
To resolve this, you need to ensure that *any other* DTC's are cleared, then clear this.
Also, I assume you are attempting to clear from the ECU? You also need to talk directly to the TAC module and clear any DTC's on that end. (e.g. you need to clear TAC module, then ECU for this to go away; otherwise, it will go away on its own after a few drive cycles.)
If you threw a Tech II on this, you'll see that the code is not current, etc.
P.S. Don't mind my 4 posts since the year 2004.... I originally posted on this forum back when Magnus was trying to do Open Source and was kicked when warning people he was going to screw them..... Now I'm back, again, but hopefully this one really stays open source. What's old is new again.
I just did a test-write to trigger the code, and then sent two commands, twice each, to try to clear it:
68 6A F0 04 - I don't see responses to this but I am not using a Y-cable right now so I'm only seeing what the AllPro recognizes as responses.
6C FE F0 14 - I see responses to this coming from a variety of modules, including the PCM. The PCM responses to this both times, with 6C F0 10 54. Which you'd think would mean the PCM is clearing the code, but the MIL stays lit.
I also tried clearing the code using the Torque app for Android, but that didn't work either.
It doesn't affect driving at all, and I'm sure it will go away after 3 ignition cycles, but I'd like to get rid of it after every flash, so that users don't think something is actually wrong.
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P.S. Don't mind my 4 posts since the year 2004.... I originally posted on this forum back when Magnus was trying to do Open Source and was kicked when warning people he was going to screw them..... Now I'm back, again, but hopefully this one really stays open source. What's old is new again.
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Free tools for editing the 2008 and up stuff just don't exist due to how the VE tables are built. I know a couple of people that have spent a great deal of time trying to get Tuner Pro to deal with the tables and determined it just wasn't capable. There are tools out there that are capable but nothing that's free.
There also are no good methods to recover the E series pcm's from a failed flash in the same manner there are with the P01 and P59's making it much riskier to work with.
I am however looking into expanding coverage into the V6 cars that used VPW data as well as the 97/98 LS1 pcm's.
There also are no good methods to recover the E series pcm's from a failed flash in the same manner there are with the P01 and P59's making it much riskier to work with.
I am however looking into expanding coverage into the V6 cars that used VPW data as well as the 97/98 LS1 pcm's.
2156 OS, the XDF is with all your source code on github. It's accurate it seems, just in weird units. A VE of 43 seems to be 1.00 and then everything else is a multiple of that. 86 = 2.0 etc. So if there's no way to change it easy I can use a spreadsheet to recalculate it to terms I understand.
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You'll find the V6 cars slightly frustrating since everything is in one module meaning even a minor code change results in different mappings. Also, the ECU can brick very easily due to the all or nothing nature. With that said, you can get away with writing only part of the flash as long as you take precautions to ensure that you are writing the same Cal to the ECU.
As far as the editor concerns with newer modules. That isn't a problem, should chat.
As far as the editor concerns with newer modules. That isn't a problem, should chat.
Probably, mostly. However, that kind of thing takes a lot of work, so it won't all happen quickly. And for really complex stuff, it can be pretty close to impossible to figure it out, but there's still a good chance we can figure out enough to be useful.
With my Subaru, for example... I found some tables for their wall-wetting modeling (also called "tau") and was able to figure out about half of it. That was enough to make a big improvement. With the stock calibration, about one second after hitting full boost, AFR would dip rich for another second, like into the high 9s when I wanted 11:1. I found that the wall wetting code as causing half of that problem (you can data log it). After some work I was able to zero it out at high load, and now it only dips to the mid-10s or so (and logs show wall-wetting compensation staying at zero). And then I posted a thread about how to find those tables, and some other guys who do reverse engineering on Subaru have found those tables for a bunch of other models and years.
It's enough of an improvement that the engine no longer feels like it's losing power during that dip. However if I'd been able to really figure it out, I might have been able to make it pull the AFR leaner, to counteract whatever is causing the remaining rich dip, and solve the problem completely. But reverse engineering is hard, and getting AFR to stay in the mid-10s made such a big improvement that I didn't have much motivation to keep working on it.
With my Subaru, for example... I found some tables for their wall-wetting modeling (also called "tau") and was able to figure out about half of it. That was enough to make a big improvement. With the stock calibration, about one second after hitting full boost, AFR would dip rich for another second, like into the high 9s when I wanted 11:1. I found that the wall wetting code as causing half of that problem (you can data log it). After some work I was able to zero it out at high load, and now it only dips to the mid-10s or so (and logs show wall-wetting compensation staying at zero). And then I posted a thread about how to find those tables, and some other guys who do reverse engineering on Subaru have found those tables for a bunch of other models and years.
It's enough of an improvement that the engine no longer feels like it's losing power during that dip. However if I'd been able to really figure it out, I might have been able to make it pull the AFR leaner, to counteract whatever is causing the remaining rich dip, and solve the problem completely. But reverse engineering is hard, and getting AFR to stay in the mid-10s made such a big improvement that I didn't have much motivation to keep working on it.
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Mostly because now that I have a tool that can read and write to my car's PCM, I want to spend more time tinkering with the car and less time tinkering with the tools.
But if anyone wants to work on a different series of PCMs, I'd be happy to help.
But if anyone wants to work on a different series of PCMs, I'd be happy to help.