Can you plug in with a scanner, and read live data?

 

Well, a known good PCM to try might be a good idea. It may also be a good idea to find a pin out and double check that keyed power is making it to the PCM.

 

I don't have any of the equipment you speek of.Is it possible it could be the ign. switch ? thanks Jack

 

Could be any number of things... throwing parts at it till it all starts working though is going to get expensive in a hurry.

Is it driveable?

 

Its a cummins it just needs fuel to run.Its the 12 valve with mech injectors.It starts out in 3rd gear unless I shift threw the gears myself.It runs the same other than I don't have ac or speedo or tach. It also doesn't have overdrive cruise its an auto trans.I would think that it is just one common thing that can cause all these things to stop working all at the same time.

 

All of which are controlled by the PCM... I was hoping you had the more common air gap issue with the crank sensor, or even the less common bad sensor. But the PCM is likely fried, I don't see that very often at all, but I have had it happen to my personal truck. It sucks, but that is likely your culprit. I would test for good constant power and keyed power at the PCM to be sure that it's not a simple wiring issue. Just need to find a haynes manual or factory service manual to look up which pins you need to check for power on.

 

Now if the pcm is fried.is it like a Nissan where the replacement has to come from another truck with the same production date.Or is the fact that its a desile change that..Would a pcm from a ram 150 auto with a gas motor work.I have a buddy with a 99 ram 250 with the 10 cly gas motor.If you think that would work I could use it for a test.i also have another buddy with a 2 wheel drive 318 auto or do I need one out of the same truck

 

Needs to at least be a diesel...... trans won't matter. (but might set some codes for stuff that ain't there.....)

 

96 & 97 Diesel with an automatic would really be your only options. 95 was OBDI, and Dodge changed the dash as well as a few other things that makes the 98 PCM incompatible.