Hi Guys,
I have picked up a used 0411 PCM from an 02 Suburban for my LS swapped BMW in attempt to fix my transmission issues. This new 0411 PCM is using O.S. 12216125.
This will be to replace a 4896 PCM using O.S 12212156. The tune I am currently working with started from this PCM and is running the engine great, but will not control the 4L60E transmission properly.
As soon as the engine starts commanded gears jump all over the place from 1 to 4 then 2 or 3, with no logic or reason. Attempt to drive and the car immediately shifts up through the gears way, way, too early.
I have replaced all the trans solenoids and pressure manifold, I have confirmed good electrical connections from the PCM connector to the solenoids and pressure manifold switch.
I have no PRNDL on this car but I do have a P/N switch on the shifter grounding blue pin 34 when in P or N.
I am now suspecting I have a bad PCM that is somehow grounding the trans solenoids when it is NOT being commanded to by the tune. It seems fine with key on, engine off, but as soon as the engine starts the commanded gear does crazy things.
What is the best way to transfer my current tune to the new PCM?
Can I just do a Write Entire?
This should cost 2 credits right?
To be sure my tune is not causing the transmission problems, would it be best to use the stock tune in the new Suburban PCM and manually edit the engine tables and various values to match my current tune? Leaving the transmission controls stock for now. Reason I would want to do this is in case the transmission part of my current tune is corrupt somehow, if that's even possible.
This should also cost 2 credits, correct?
Thanks guys, this problem has really got me stumped......