Attention: TDR Forum Junkies 
I am having a problem with my PCM. I was having 2nd and 3rd gear starts. After trying quite a few different things to solve my problem, Bill K sent me up a different PCM to try. This was a cure for my limp - mode problem. Transmission shifts very well now. But because it was from a 97 none of my factory gauges work. I will check fuses in the morning.
Now for my question... ... . I have already had my original PCM reprogrammed but that did not solve my limp mode. The Stealership that did the reflash said all the latest programming was installed, including TSB # 21-04-00. So what gives??? Why would one PCM work and not the other. I do not really want to buy another PCM because I can not comprehend what would be "broken" on mine when it is only programming being entered.
This is a cut and paste of TSB# 21-04-00. I took my truck in to have this TSB and only this specific TSB done, but they just refashed me and said that this data was entered as part of the reflash. What's your opinion?????? Any hints???? Good ground to PCM? Does yours have a braided ground strap from engine to the PCM? Also Bill was saying when doing work with the PCM I should disconnect the batteries. Is this to let the PCM forget what it learned or is it for the safety of the PCM? Like I said, I would really like to use my original PCM so any help would be great.
On edit... ..... I just had a brain fart. Actually a good idea maybe. Would it be possible for me to put a resistor or some kinda power booster depending on what wire # 29 (light green and white wire) needs. This would be the wire that sends the signal back to the PCM after it gets its signal from the governor pressure solenoid. I think that may be the wire that needs some tinkering with. It would work to fool my PCM again, and take care of the TSB below. Am I a dreamer? Thanks... ...
Erroneous MIL illumination for P1763 – Transmission Governor Pressure Sensor Volts Too High.
Some vehicles may exhibit a MIL illumination with a Diagnostic Trouble Code (DTC) of P1763 – Transmission Governor Pressure Sensor Volts Too High. The vehicle operator may experience slower than normal vehicle accelerations because the transmission may have temporarily entered its third gear “limp-In” mode as a result of the DTC. The “Limp-In” mode may last until the vehicle owner cycles the ignition key. The technician may not detect a problem with the automatic transmission during a diagnostic test or test drive.
The MIL is caused by an increase in hydraulic pressure. The increased hydraulic pressure is the result of a new valve body machining process, which entered into production January 1, 1998. This condition will occur most often with vehicles that were built between January 1, 1998 and December 18, 1998.
Vehicles built prior to January 1, 1998 may also experience this condition if the valve body or the transmission assembly is replaced with components built after January 1, 1998.
This bulletin involves selectively erasing and reprogramming the JTEC Powertrain Control Module (PCN) with new software
Now for my question... ... . I have already had my original PCM reprogrammed but that did not solve my limp mode. The Stealership that did the reflash said all the latest programming was installed, including TSB # 21-04-00. So what gives??? Why would one PCM work and not the other. I do not really want to buy another PCM because I can not comprehend what would be "broken" on mine when it is only programming being entered.
This is a cut and paste of TSB# 21-04-00. I took my truck in to have this TSB and only this specific TSB done, but they just refashed me and said that this data was entered as part of the reflash. What's your opinion?????? Any hints???? Good ground to PCM? Does yours have a braided ground strap from engine to the PCM? Also Bill was saying when doing work with the PCM I should disconnect the batteries. Is this to let the PCM forget what it learned or is it for the safety of the PCM? Like I said, I would really like to use my original PCM so any help would be great.
On edit... ..... I just had a brain fart. Actually a good idea maybe. Would it be possible for me to put a resistor or some kinda power booster depending on what wire # 29 (light green and white wire) needs. This would be the wire that sends the signal back to the PCM after it gets its signal from the governor pressure solenoid. I think that may be the wire that needs some tinkering with. It would work to fool my PCM again, and take care of the TSB below. Am I a dreamer? Thanks... ...
Erroneous MIL illumination for P1763 – Transmission Governor Pressure Sensor Volts Too High.
Some vehicles may exhibit a MIL illumination with a Diagnostic Trouble Code (DTC) of P1763 – Transmission Governor Pressure Sensor Volts Too High. The vehicle operator may experience slower than normal vehicle accelerations because the transmission may have temporarily entered its third gear “limp-In” mode as a result of the DTC. The “Limp-In” mode may last until the vehicle owner cycles the ignition key. The technician may not detect a problem with the automatic transmission during a diagnostic test or test drive.
The MIL is caused by an increase in hydraulic pressure. The increased hydraulic pressure is the result of a new valve body machining process, which entered into production January 1, 1998. This condition will occur most often with vehicles that were built between January 1, 1998 and December 18, 1998.
Vehicles built prior to January 1, 1998 may also experience this condition if the valve body or the transmission assembly is replaced with components built after January 1, 1998.
This bulletin involves selectively erasing and reprogramming the JTEC Powertrain Control Module (PCN) with new software
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