97 2500 no tach, no ac, no volts ,no cruse all items went off at the same time. Changed the alt, no luck went to the local auto store, alt checks out fine....now someone asked for me to check the fuseable links. Schematic dont show one between the PCM and alt. it there another one I can't see? Or do I just pony up and get a new PCM. Any advice would be helpful

 

Does it run? Sounds like an ASD event..... (auto shutdown relay)

 

Runs great, just have to charge it In the garage every other night. Is there a voit reg. somewhere?

 

The voltage regulator is integrated in the PCM of these trucks. So if that is indeed the problem you're hosed and just got bite the bullet to get another.

Make absolutely 100% sure it's the problem before you go shelling out the money for a new PCM.

 

Those aren't cheep, s.o.a.b. I thought so... What do they run 400 or so?

 

Have alt tested befrore you do anything else. Fully charge battery and see what the Key off amp draw is> THis may indicate problem.

 

This is the 2nd alt I have tried also, tested the alts. at the local auto parts store both check out fine with a load.

 

Do you have access to a high end scanner that can monitor PCM values? If so, you should be able to see alt output, and if it is volt regulator, it would be visible there. Otherwise, check key off draw. SOmething may be pulling it down. Also double check the numerous chassis and body grounds to make sure connections are clean and tight.

 

Good info I'll check all ground in the am.. I'll ave to take it somewhere for testing PCM thanks