1998 2500 recently had the cab replaced due to roll over.Truck is almost all together,but the tranfer pump runs with the key off.Also,the alternator is not charging and the guages in the dash are not working.The truck has an after market higher performance pump,(brand unknown).Following the wiring,it appears that the pump is wired into the factory wiring harness.I have found that by disconnecting the ECM fuse 2,the pump stops running.It appears to me that the Power Train Control Module should supply the power to the pump when the key is turned to the run position.Is this correct??
I can get the alternator to charge when I ground the field circiut.This could be a broken wire issue to the ECM,but with other issues, I believe the Power Train Control Module may be the culprit.Correct me if I am wrong,but does the Engine computer monitor coolant temp and oil pressure??If so,does the Engine computer send this info to the Power Train Control Module??From there,does this information then get sent to the guage cluster for them to operate??
Can you tell me where the Power Train Control Module would be located??Assistance in solving these issues would be greatly appeciated.
chucks

 

Not 100 percent sure on the tech side but id start by checking you grounds. The PCM is located on the passenger side of the truck inside the engine compartment right behind theinner fender. It should have its own ground as well. The ECM is located on the side of the engine block, on the drivers side underneathe the injection pump and behind the fuel filterr canister. Also, in the main fuse box, there is a jumper fuse. Its a 140 amp fuse. It connects the battery and alternater. Follow the battery wire into the fuse box and you'll see it. Check and see if its blown cause it can cause the power problem. Gauges could be aground issue or even. A bad ignition switch