I am running a 5 speed truck with a mopar pcm. It seems the mopar pcm is for an auto truck. Can someone please tell me how to ground the neutral safety switch?

The truck is a 93 5 speed 4x4 with a swapped 318 magnum. It is throwing 45 and 37 codes.

 

Find the neutral switch wire in the harness (leads to cavity/pin 30 on the PCM), and run it to ground. Should be a brown wire with a yellow stripe according to the sticky FAQ (PCM connector diagram). That's if you have the wiring harness for an automatic, as I do in my 5 speed Magnum swap. If you have a wire harness for a manual truck, you may need to add a wire to that position on the connector which may require finding a connector pin and inserting it into that cavity (30).

 

ok so this would be a v6 manual trans harness. I do have more pins. So all I need to do is run a wire from the pcm and ground it?

 

That's it.

 

Thanks for the help ragged89. I'll go get it done.

 

The wire is ground. Just curious, after I take it for a drive will the pcm still throw trans codes?

 

It may, if the PCM is looking for a lock-up torque converter (automatic trans). I'm a little rusty on that one, and too short on time at the moment to review it (sorry). It shouldn't cause any driveability issues though and the Park/Neutral shouldn't be a problem once its grounded.

 

Not sure how similar the 90 and 93 pcm's are, but on my 90, the lockup had nothing to do with the pcm, other than the ground signal to fire the solenoid. However, there's a speed switch on the automatic transmission tailshaft (where the speedo cable connects) that does feed the pcm that's used for the lockup and overdrive solenoids....The absence of that speed switch might throw a code, but nothing you can do about that. In my re-wire I kept the speed switch but since I removed the pcm, it goes nowhere but to the engine connector.

 

Thanks for jumping in robertmee, I couldn't recall where the lockup/overdrive signal originates.

I'm actually not sure which PCM he's using, maybe the Mopar HP? Not sure which year either, but even up thru '95, I know there's not a whole lot of talking between the PCM and transmission.

 

If the PCM is being removed, but if you still want lockup and overdrive, there's always the method used by PATC for their 727/518 upgrade kit ..

https://transmissioncenter.net/shop/...iring-diagram/

RwP