Cadillac Powertrain Control Module (PCM) Tuning Discussion, 6.5L Turbo Diesel EPROM Programming - AJxtcman and other members in Cadillac Engine Technical Discussion; I know this vehicle is not a Cadillac, but I was reading a post from 2009 by AJxtcman and he ...
6.5L Turbo Diesel EPROM Programming - AJxtcman and other members
I know this vehicle is not a Cadillac, but I was reading a post from 2009 by AJxtcman and he stated in his post that he was able to program the EPROM for a 1996 Hummer H1 6.5L Turbo Diesel. I have a 1995 Hummer H1, with a 1996 6.5L Turbo Diesel engine and L480E transmission. Most of the parts on this vehicle are OEM GM parts. The transmission is stuck in limp mode, and I am not able to read any codes from the TCM, even with the pins jumped (diagnostic mode); the check engine light just stays solid and does not give the 12 code.
I ended up replacing the TPS, as the old unit was reading 0.0V when it should have been reading 0.68V with the ignition on and the engine off; the new unit works flawlessly. After disconnecting the batteries and reseting the TCM, I am still not able to enter diagnostic mode and the truck is still in limp mode. The service manual stated that this is usually caused by a bad TCM, so I ordered a re-manufactured one (Part # 16196390), which should arrive Monday, 2/27/2012. The next step (if this does not correct the problem) is to replace the PROM. Would anyone here be able to assist me by reprogramming the PROM?