2004 quad 4x4 4.7
Had the no bus issue. replaced pcm, truck started fine. Alternator seemed to be laboring, checked voltage 17.5, then down to 15 then back up to 17.5 again. Shut truck off, now have the no bus issue again. Truck will not turn over.Tried resetting the pcm, no change. Did I fry the pcm with an alternator that's putting out too much voltage.

 

Possibly. 17.5 is VERY high.

When you say won't turn over, just to be clear, it won't crank? Or it won't start?

Check for a shorted/grounded alternator field leads.

 

it won't crank

 

If the voltage was truly 17.5 you likely have some damage. First off, how are the fuses?

What does work? Lights, etc?

Can you pull any codes?

 

All fuses a good, only codes are cluster ones 920,921,960, 999. I had the same codes with the old pcm.when the truck started it was running fine except for the lights being a bit on the bright side and the engine light on.

 

Even with a dead PCM it should crank - unless Dodge did something really weird with the wiring in '04.

Unfortunately, I don't have a wiring diagram for '04.

Check for power at the starter. Have someone work the ignition switch so you can see if the solenoid is getting power when in "start."

 

no power on solenoid...
replaced alternator old one failed bench test. plugged in obd ll could not connect, key on or off. PCM dead???? or is there some way to bring it back to life.

 

What does have power? What happens now when you turn the key? Do you hear a relay click in the PDC? I'm going off of a 2001 diagram so bear with me here. Is there a relay or a fusible link for the starter in the PDC?

Check pin #16, it may be a pink wire, for power at the data link connector.

 

When I turn the key all the dash lights come to life, the voltage gauge does not move at all, oil pressure moves to the 0 position, THere is a relay for the PDC, have already change it, don't hear any click in the relay in the PDC. I think there is power on the data link as the OBD comes to life when I plug it in, but it cannot connect. Have another PCM to try, its not flashed, Just seeing if I can get it to crank.

 

Try starting in neutral. Maybe there is an issue with the neutral safety switch.

You should hear, at least in earlier years, the starter relay in the PDC click when you turn the key.