I just purchased a 97 2500 4x4 cummins Automatic at an auction. I have an issue. The tach, speedo, cruise, OD, are not working. I have been doing some research and just wanted to get as much info as I could before I start buying parts. I have taken off the crank position sensor and cleaned it up, would like to know if there is a way to test it before i re install it.

Ok here is the way to test your CPS. Black/blue tracer is the sensor ground wire. It should OHM close to zero to the battery ground. Tan/yellow tracer is the 8 volt power feed to the sensor. The voltage regulators on the PCM's are kind of loose. This voltage can vary around some. Gray/black tracer is the signal wire. If the sensor is on a smooth section of the balencer there should be little if any voltage showing. When the sensor is on one of the air gaps it should show around 5 volts.

Sounds good I will check this right away, I assume that the ignition would need to be in the run position? I also found a broke wire on the passanger side in the very front of the fender it goes to the top of the front axle then not sure after that. But I need to take the plow mount off to get to it.

Yeah, key on. And that wire sounds like the 4wd light sensor whatyoumacallit. http://articles.mopar1973man.com/general-cummins/39-transmission-systems/80-central-axle-disconnect-cad-system-troubleshooting

I would also like to check the PCM, my brother has the same truck but its a 96. Can I swap the PCM to see if it works in his truck or are they not compatable?

I'm not 100% on that. The 97'+ have OBDII and I think that would make them differ to the point that you couldn't swap them. Other than swapping one with the same spec truck, I don't know how you would test the ECM. Have you checked every single fuse?

Well I ended up swapping them and that was the problem, everything worked except for the cruise. So i will be purchasing an PCM.

Put in the new PCM, eveything but the cruise and fuel shut off works. I took the shut off solenoid off and it seems to work fine but the linkage it goes to will not move by hand? I hope there is a resonable explanation for this? I will be diggong into it further tonight, maybe the linkage has been in the same place to long and needs to be cleaned up and lubed? If anyone has any advice it would be greatly appreciated!