View Full Version : 6.5L Turbo Diesel EPROM Programming - AJxtcman and other members

02-22-12, 12:42 PM
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?

Thank you so much in advance!

Herrick D.
Roanoke, VA
1995 Hummer H1 6.5L TD

02-23-12, 06:48 AM
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