Cobalt 4T45E Tranmission Adaptive Pressure Shifting

[klotzy_550]

Good morning,

I have a 2008 Cobalt with a TCC that like to lock/unlock on flat ground and a constant speed. (I have a log of this). I tweaked some of the TCC max and min DC values and the problem went away for about 650 miles (one trip). I did some basic tests on my TCC and it seems to behaving correctly. I have read that the T42 has had logic issues with the Transmission Adaptive Pressure Shifting logic. I want to see if my problem is actually TAPS or something else. The reason I believe it went away at first is because that was the first tune I have ever put on my module thus resetting the TAPS logic. Now that I have ran some time with it the logic is recorrupting like a corrupt memory address. If I do a write entire will that reset my TAPS values again? or will it harm anything? My thoughts are if I can confirm that it is corrupt logic, Ill just buy a different TCM which brings me to my next question. Can I buy a T42 from the bone yard with matching service numbers and re-vin it for my vehicle? Then write entire to have the proper calibration on it? Or is it just easier to order one programmed for my vehicle specifically?

If anybody could give me some insight it would be greatly appreciated!

[Area47]

consistent locking and unlocking is typically a sign of the converter shitting the bed.

[klotzy_550]

consistent locking and unlocking is typically a sign of the converter shitting the bed.

True, however, upon uploading new cal it disappeared? I didn't make any modifications to the TCC control initially upon uploading. It should also be noted that I only have this issue when using cruise, If I drive w/o cruise it will remain locked