Help! LY6/6L90 Swap

[1bad68cat]

Hello All,

I just completed the install of a LY6/6L90 into my brother's 66 C10. I had a couple of hiccups along the way, but was able to solve them. Now I have one that wants me to pull my hair out.:banghead: Initially, I had a problem with the speedo not working and the transmission not shifting. I called John @ Speartech and he gave me a couple of suggestions. Long story short I found that the seal that seals the TCM to the trans case was not fully seated therefore not allowing the TCM harness to make consistent contact. After I had fixed the seal problem, everything seemed to be working properly until I shut the truck off and restarted it. The truck did not want to shift again (although the speedo still worked unlike before). I can get it to shift again if I remove and reinsert the TCM harness or battery cable, but I do not want to be doing that everytime I shut the truck off. I have used the search function here on Pro-Touring but have not found anything similar to my problem. Anyone who did this swap run into a problem similar to mine? I have an email to Speartech and hope to have an answer tomorrow. This is the last remaining issue and the truck can go back to daily driver duty. Any :help!: would be greatly appreciated and thanks in advance.

Robert

[bsharpe]

We need more information to help. Did John tune the computers and do the wiring? Are both computers from the same vehicle? How are you shifting the trans? It seems like a tcm problem since it resets when it looses power but i dont know. I have not got to the electrical part of my swap.

[1bad68cat]

John, reworked the harness and reprogrammed both the PCM and TCM. The engine and transmission combination are from a 2007 Silverado, but not from the same truck. I am using an Ididit retrofit column I bought through Frank @ Prodigy. I elected not to run the TUTD feature.

[bsharpe]

Your set up sounds similar to mine. I am doing the wiring and tuning myself but my project is not running yet. I have not seen this problem before. I would contact John. It almost has to be a wiring or tuning problem. Sorry i cant help

[TBMSport]

Did you resolve it? I had a similar problem when I did my conversion. Don't remember if the code was the same...though. It refused to start at a gas pump. After clearing the code it restarted...but that got old fast. I had to reprogram the ECM to make it work normally.

[1bad68cat]

Did you resolve it? I had a similar problem when I did my conversion. Don't remember if the code was the same...though. It refused to start at a gas pump. After clearing the code it restarted...but that got old fast. I had to reprogram the ECM to make it work normally.

Unfortunately I have not resolved the problem. I get a P02534 code every time I shut the truck off. I emailed John this past weekend with the results of the test he wanted me to do, but I did not see anything out of the ordinary. Hopefully he may see something I'm not. :fingersx: I may have to just suck it up and take it to the dealership. :confused::banghead:

[TBMSport]

I'm gathering that there is a communication issues with your CANBus settings, so the transmission (or ECM) is triggering codes and putting the trans in limp mode (3rd gear only) until it's resolved. I am assuming a typo and you meant a P2534. That's an ignition voltage low signal. I think the problem is with your Ididit steering column ignition wiring. Either you have a faulty connection or the ignition voltage/resistance values are not like the '07 truck it came out of and therefore triggering the redundant anti-theft/systems check programming features to freak out. Something that should be easy to resolve with the right software.

What tuning program are you using? If you have EFILive (or know someone who does) I could walk you through some troubleshooting ideas that should resolve the problem.

[1bad68cat]

I'm gathering that there is a communication issues with your CANBus settings, so the transmission (or ECM) is triggering codes and putting the trans in limp mode (3rd gear only) until it's resolved. I am assuming a typo and you meant a P2534. That's an ignition voltage low signal. I think the problem is with your Ididit steering column ignition wiring. Either you have a faulty connection or the ignition voltage/resistance values are not like the '07 truck it came out of and therefore triggering the redundant anti-theft/systems check programming features to freak out. Something that should be easy to resolve with the right software.

What tuning program are you using? If you have EFILive (or know someone who does) I could walk you through some troubleshooting ideas that should resolve the problem.

Actually I still have my ignition switch in the dash. John from Speartech did all the programming. I did conduct some test he suggested and the only discrepancy I can find is that the no. 4 pin (ignition wire, pink) on the TCM connection is 1V lower than the no. 12 pin (battery, red/wht). The voltages are 12.6 and 13.6 respectively. Didn't think this could be the issue because the condition required to set the DTC is voltage below 2V for more than 10s. I am still waiting to hear back from John to see if my assumption is correct and to find out if I need to look elsewhere for my problem.

[TBMSport]

You're going to have to get someone who can go inside the TCM. Not much John can do unless he sold you the trans with preprogrammed TCM. With EFILive you have the ability to set the DTC Action to a simple non-emissions check engine light or shut it off completely so it will simply ignore it.

[1bad68cat]

You're going to have to get someone who can go inside the TCM. Not much John can do unless he sold you the trans with preprogrammed TCM. With EFILive you have the ability to set the DTC Action to a simple non-emissions check engine light or shut it off completely so it will simply ignore it.

I was looking into getting EFI Live or HP Tuners. Looks like I have a good reason to now. John did actually reprogram the TCM. I'll ask if maybe a function was not turned off. Although, I am not really looking forward to removing the TCM again if that is the case. If the DTC is ignored, won't the transmission still go into limp mode?

[TBMSport]

A tuning software is a MUST if you're dealing with a modern EFI drivetrain. It'll pay for itself in no time flat!! Just look at see how many you can find used in any given forum's classified. I'm biased to EFILive because it's cheaper if you plan to do a lot of tuning. Last I checked HPTuners charges you credits each time you make a change, even if its the same vehicle module. Plus, I can't offer any type of assistance if you get HPTuner...you'll have to ask the someone else here or hop on HPTuners' forum.

RE: DTC Ignore. The computers ALWAYS recognize a DTC as it's part of the basic emission related programming. What the modules do about it is a different matter. So if you tell it to ignore it, it will act like nothing ever happened. Not necessarily ideal in a new car where a multitude of variable are process for ABS, suspension, airbags, etc...but in a retrofit that doesn't exist.

[bsharpe]

Any updates?

[1bad68cat]

I picked up EFI Live and had ignored the code. It worked, but I'm still trying to figure out what is causing the code.

[hotrodrev]

I know that you have probably checked this already, but this sounds like the ignition power to the module is not start/run hot. This may be why you can't get the trans to work until the engine is running and the module is hard shocked.

[1bad68cat]

I haven't had much time to diagnose because of work, but I did check the wiring for correct operation. In talking with John, it almost seems like the TCM is not shutting down when I turn the truck off. I have checked power at the TCM connection per John's instructions and everything is good there. My family has put 5000 miles since ignoring the code with no hiccups what so ever. I've taking it on a few long trips with no concerns if it is going to breakdown. To me it seems as reliable as a new vehicle, which is what I was after so my dad could drive it daily. But still, knowing it is there bugs me and when I have time I will be digging into it more.

[Poorhousenext]

Just happened to check out LSX and saw your post. About two weeks ago I ran across a similar post on LS1 tech with same code. You might want to check out the thread below. Code seem to be related to a problem with TCM shutting down before ECM. Seems both need to shut down at same time the way it reads.

http://ls1tech.com/forums/conversions-hybrids/1459666-l92-6l80e-swap-trans-limp-mode-dtc-p2534.html