t87a swap kicked P0700 p27Ax codes
I have a 2018 Camaro 1SS and I recently got a new T87A TCM for it. so tonight I got my new t87a TCM in today, installed it, went in and deactivated the torque management and now I have a P0700 code along with a few others all related to the transmission/TCM like P27AA, P27AB, P27AC, P27AD. is this because of the new TCM, did I mess up on the TCM swap somehow? or is this because of something else?
Your TCM is missing the solenoid characterization data for the transmission it is controlling. This information is programmed when GM's service tools flash the TCM. If you didn't do this step before installing the TCM in your car, that's why you're getting these codes.
I found that out last night in my research. do you know if I reinstall the stock the TCM will I be able to use the Beta VCM to carry over those characteristics? that's my plan to correct it as of now
I just installed a T87A and once I installed it I tried to enter the transmission TUN (transmission Unique Number) with the calibration for the current vehicles transmission. I did this with the GM MDI2 and it appeared to go through, but I get all the P27?? calibration error codes that you did. So what did you do to eliminate them? I looks like there would be step by step instructions that come with the TCM. I have replaced and programmed these TCMs using GM and it is easy. What I found odd is the T87A unlocked TCM has no VIN and no program date in it. Is it possible that when we log on to GM site with the TUN it declines uploading the calibration to the TCM from GMs web site? So If I can't get the TUN files online how do I transfer them from the old TCM? What if I need to replace the valvebody or transmission later on, how do I enter the TUN then?Originally Posted by markbyers39
what I had to do to eliminate them was drive the car in various ways and in all the all modes, basically reteach the TCM. I drove the car for about 3-4 days and it relearned everything then the codes went away on their own. as for the valve body install, I'm going to assume that it'll be the similar but the TCM will have the learning done already, so you'll just have to enter valve information. as for the removal of the codes, like I said, you just have to drive it. it'll relearn
If I tell the customer to drive it a few days and it might relearn and eliminate the DTCs, I'll be married to that transmission the rest of my life. When I replace a TCM, a transmission, or a valvebody on the 8L90, all I have to do is program the TCM and enter the TUN number using the MDI2 factory tool, then I do a fast learn (and it takes better than 15 minutes) and thats it......no codes. I feel like if I could program it with the GM factory tool, it would write the VIN# and program date, and the TUN would be accepted into the TCM. I'm willing to write over the TCM but GM has me blocked because it has the latest software already, and it won't allow me to re-write over it. Now I could program it to a different VIN that has different software, then re-write it again to the needed VIN, BUT if I try that I have 2 questions. 1, will the GM tool allow me to program it more than once, 2, If I attempt this will the HP Tunned T87A remain UNLOCKED?
Did this work dealing with a similar problem now
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