Ok truck is a 1997 dodge 2500 turbo diesel. Three days ago the new alt stopped charging, the tack and speedo stopped working, along with the a/c and intake heater system. I rechecked the new batteries, starter, alternator and bell housing (new clutch). Everything seems a ok. With that down I changed the ignition switch which did nothing. I then moved on to the pcm. I swapped the pcm into a clone truck and it worked fine. I then removed the pcm and started the clone truck. It now had all the symptoms of my truck. So the pcm is good but does not work. I checked all the fuses. Found some fuseable links witch tested good. What is the deal? What should I do? Is there a relay pack somewhere I am missing? Is there a diagram of the pcm harness somewhere?

Please please please help me kill this electrical gremlin!!!!!!!!!!!

 

Cornfused here.

Your PCM worked in the other truck, or didn't work?
Other trucks PCM worked in your truck, or didn't work.

Alternator, A/C, tach and speedo point to the crank sensor.
If the PCM doesn't think the engine is running, it won't let the alternator charge or the A/C work, and obviously the tach won't work since it doesn't think the engine is running.


phox

 

Puzzman -- try reading through this thread, might be helpful, https://www.dieseltruckresource.com/...ad.php?t=56565, Or pm infidel, he helped me get my 97 going with similar issues,or here https://www.dieseltruckresource.com/...ad.php?t=62408