After HPT TCM swap, CCM not working as programmed

[andrewzpsu]

After swapping to the HP Tuners TCM, the CCM (module that controls the dual mode exhaust) is not functioning properly in my 2018 ZL1. It is reading that it is in performance mode 0 (tour) and will not change into other modes by either the mode selector or the display screen. I haven't noticed this on any other cars, but truthfully mine is the only one I've paid attention to since I tuned my CCM.

Anyone else have the same issue?

[andrewzpsu]

Just confirmed with another ZL1 at the shop that has the TCU upgrade, that the dual mode is stuck in tour mode.

[tunerpro]

That is very odd. Did you use the original TCM or a different one? Do the VINs match on the TCM and other ECUs? I ask because there was a GM bulletin back in 2010 or so when the first "Global A" vehicles arrived in the market that said the ECM, TCM, CCM and a few other ECUs made up the "security model" (was it called an "Environment ID"? I dont recall). It said something to the effect of if you swap any one of these modules it can cause security failures. I know it's a stretch, just an idea.

Another question - if you put the OE calibration back in the TCM do you get the exhaust mode selection back? And lastly, did you try disconnecting / reconnecting the battery?

[cmitchell17a]

I bought a complete unlocked T87A, in my 2017 camaro SS, when I used the replace TCM function, HP tuners scanner gives an error message that the read failed, but it still might work. Anyway everything seemed to work with my new TCM, but I never could read it (which even unlocked T87As might not be able to be read?).

So about a month later the check engine light comes on and now a permanent DTC is set for missing transmission solenoid #1 flow data. You can't clear it either since its permanent. Also I have noticed the same thing you were describing that the exhaust will get stuck in sport and won't go back to tour. It will eventually switch back after a restart though, I also have reflashed my CCM.


Also, the "security failures" you are talking about, would that mean the car would refuse to start? or it would potentially leave you stranded?
I found this:
https://gm.oemdtc.com/TechLink/TechLink2010Feb.pdf
which dosent really give that great of a explanation and is kind of confusing.

I actually haven't tried disconnecting the battery and try to reset everything, that may be worth trying.

[andrewzpsu]

UPDATE: Well I may have just been a little too anxious - and paranoid. I've long suspected some issues with the generated TCM file from HPT - still curious as to why we can't read the actual tune, even after the unlock service has been performed and even the first write. But nut shell is the CCM is working again after a few key cycles.

So, since I've programmed my CCM, I've been paying attention to the modes its in. Turns out, I jumped the gun. With some engine writes on all the dual mode cars, the CCM seems to default to Tour Mode in terms of the exhaust mode and doesn't function normally for a few key cycles - I've know this to be true in the past, but was never logging it before. So with my car, I was logging and when I saw the mode was not changing I was a bit more paranoid, but with a little bit of time, the CCM is functioning normally again.