I just bought a 92 d250 and I have a few problems with it.The wait to start light quit working when you turn the key on but after you start the engine it comes on and stays on.Engine starts and runs perfect.Not sure what would cause this.I also dont have a check engine light when the key is turned.I was wanting to see if I had any codes but there is no light to flash,I have not pulled the dash out yet to check the bulb.All fuses are good.My overdrive is not working either.Anybody know where the pcm is on these trucks?Any help would be appreciated.Thanks John

 

sounds like a PCM problem, or a wiring problem.

first step would be to check the body ground right by the battery terminal.

 

Ok where is the pcm at on these?I will check the grounds first before I start replacing parts is there a way to check it?Can it be scanned at auto zone?

 

the reason why the lights stay on on these is if the computer is signalling too high of voltage or way too low of voltage. most likely you got a computer issue. but ive also seen this happen when one of the intake heater elements goes bad as well. also check the ground the goes from the intake heater to the ground on the housing. i dont remember exactly where the pcm is but iirc its on the driver side fender well

 

oh, and there's a whole 6? sensors on the whole truck... no need for scanning, and i'm pretty sure there is nothing to be scanned anyways.

 

We have a 92 d350. The pcm is tucked inside the fender behind the battery. I got the dodge factory manual on C.D. from GENO'S Garage. I might be able to send some diagnostics from it to you. I think the C.D. cost us about $30.

 

Thanks everybody for the input.This is my first diesel and I am not familiar how everything works.

 

Welcome to the slippery slope! You'll never go back to gas.

 

updates?

 

truck is still at transmission shop no speedo or overdrive.getting new speedo gear next week mine was wore out hope to get it back next week so I can diagnose the problem with wait to start light.I just bought the truck it worked fine the day I picked it up but now its doing what I described above.