Hi guys,

I'm confused here. I need to find a wire that I can tap off that comes from the hot side of the ignition switch whenever it is in the ON or START positions. I'm stumped from the wiring diagrams, I need one I can tap easily.

Thanks for your help!

Truck is in my sig, 1996 dodge ram.

 

Dark blue wire. Should be 12 gauge. Hot in run/start.

 

Worked great!

 

So even though the engine is not computer controlled anymore, I still need the PCM so I can run my gauges as I'm not ready to get rid of the PCM altogether!

I first noticed the PCM wasn't working as my CEL didn't come on and I had all sorts of different sensors not hooked up. Then I noticed my tach or voltmetre werent working either! What wire on which connector at the PCM powers it?

Thanks for your help!

 

I should add: The fuel pump still works though!

Edit: I believe the only reason the fuel pump is running is that the ASD relay is working cuz the CKPS is hooked up.

 

For potential readers of this new thread, that have no idea of what you have done to your truck, don't you think you should have posted this in that one? Just sayin'

 

Well I checked for power from the rd/wt wire that supposedly powers the PCM and it had voltage, plugged in speedo cable and no speedometer, no ABS, but fuel pump runs.

Truck was being converted to carb with PCM left to run gauges.

CKPS, Gauge temp sensor, and oil pressure sensors are the only sensors hooked up to the PCM now, which should run my instrument cluster. I'm stumped Oil pressure gauge reads but shows 110 PSI even though it is at normal oil pressure. Maybe the PCM went bad?

 

I had an issue with my PCM where the truck would die sometimes or it would not start, no lights would come on with the key either, only code was 'power interrupted to PCM last 50 key cycles' or something like that, but I had power to the PCM at the connector. Turns out the solder for the connector on the PCM was loose and would loose contact. Just for the hell of it, try moving the connector up and down when it's screwed into the PCM and the key is on (might need someone to sit in the truck and look at the dash) if the lights come on, there is your issue.

 

Thanks for the suggestion. I tried that, no difference. Tried swapping with a different PCM, no difference. Probably a wiring harness went bad or something... Everything NOT related to the PCM works fine...

 

This is in a 96?

Oil pressure gauge, and temp gauge, are not driven by the PCM. Tach, Speedo, and possibly volt gauge are. (PCM controls voltage regulator as well, unless you have bypassed that?)