I have been looking for a schematic of the guts of the Power Train Control Module on the internet with no success, anyone know how to get one? Would be useful to fully understand for example how the fuel gauge works. Based on the obseved issues, it appears that it is also powered from the same 5V ref circuit as the evap emissions pressure sensor and the TPS. Interestingly enough, was talkingto a co-worker whose son also has a a 2001 GP, his is throwing the code for the evap emission pressure sensor (thats what their mechanic told them, wants to change it). He didnt know if there were any other codes involved, but he did say that he recently changed his oil and could now not reset the oil change reminder light. Whan I asked him how he did that he said it involved pumping the gas pedal 3 times rapidly. That was an A-HAA! moment, I'll bet he also is getting bad output from his TPS due to a root cause problem with the 5V reference power that feeds both sensors!
