Hi

I have a 2004 Chrysler Town and Country Limited minivan. It has an intermittent no crank-no start problem. All connections are good. When the failure occurs, the ignition switch is providing 12 volts to the starter relay coil but the PCM is not providing a GND to the coil. I pretty much ruled everything out other than the PCM. Have you sold many PCMs for this vehicle due to this problem? How can I be sure it's the PCM before ordering one? The problem is intermittent. The van will start fine for days then suddenly not start for days then starts again. If it was the transmission Park/Neutral switch I assume the failure would occur all the time.

Thanks for your help.

Tony Dicarlo

 

There's no real way to prove the PCM itself is bad without sending it off to be bench tested. All we can do and the way it's normally done at least by all of us DIYers is to eliminate any external causes as the problem such as the TRS (park/neutral switch) in the tranny, the alarm system and all connections and wiring. I've read of some who have pulled the starter relay up a hair and connected an external ground to contact #85 (the ground from the PCM). If the engine cranks then at least you know everything excluding the PCM and that ground wire from the PCM are ok. Then you just check continuity of that ground wire from end to end with an ohmmeter. If that's good then it's time to replace the PCM. Unfortunately it's tough to say anything is a sure bet especially on an intermittent problem. Have you tried a wire harness shake test.


"Have you sold many PCMs for this vehicle due to this problem?' Can't answer that. I'm not a tech. Few of us are. I can say I have read of the PCM as a fix for this problem on this and several other forums over the years.

" If it was the transmission Park/Neutral switch I assume the failure would occur all the time." Wish that was true but no.

 

This is not a Petrol with burnt wires near exhaust is it...

 

Good point. Well worth checking into.

 

I did externally ground pin 85 of the starter relay and the starter did crank but the engine would not start...like the fuel and/or ignition system was shut down...Thanks.