I have been having ongoing electrical issues that left me stranded last night.
I have a 92 W250, everything started when the OD stopped working. I tried bypassing the TPS with a potentiometer, didnt work, new TPS didnt help. I was able to get OD by hooking a switch directly to the OD solenoid and grounding it when I needed OD. Then I noticed my cruise no longer engaged. And last night I was driving and my battery died, found out it was not getting a charge. I replaced the alternator hoping that would get me back on the road, however it was not charging as well. Where do I start? I know the PCM has the regulator, I am hoping its not that, not sure how to check that. But I think its all related. I have checked all the grounds I could find, cleaned them, just not sure where to check next. Please help. I am trying to get out of town ASAP to help someone move.

 

Sounds like a CPS (crankshaft position sensor) issue. It is located by the harmonic balancer just to the left of the balancer (looking at engine). Look for broken wires, a loose connector at the front of the valve cover, gap set at .050". There are many posts on this.

 

Sounds like a CPS or CPS wiring problem.

CPS means crankshaft positioning sensor

Also check fusible links, relays and fuses in that order if not the CPS

 

Oops I type slow

 

Yup cps

Sent from my HTC One using Tapatalk

 

Also check the relays on the drivers side inner fender. One of those helps control the charging. Info on what relay controls what is in the Sticky.

 

YUP ! What he said ! The sticky tells you exactly how to test and correct this issue, as when I bought my first CTD, it was doing the exact same thing.


Turned out to be the relay.

 

Thanks everyone, I will get to checking that stuff! My A/C still works would that rule out the cps?

 

I changed the gap on my CPS to .50 and checked the connections, all look ok, the blk/blue wire shows ground, the tan/yellow wire shows 8.8 volts with the key on and the grey/black wire shows 5 volts, even over the air gap, shouldn't it go back to 0? does this indicate the CPS is indeed bad?

 

You all were dead on, it was the cps, thank you!!!!!!

 

Right on...glad you got it figured out. Did you have to replace it? Or just clean and regap?

 

Just for grins and giggles, read post #9

 

Wow!...Mark

 

Man I hope one day we all can be cool like "j" !

 

Ended up replacing it, darn thing wasn't cheap. On a side note how much movement is normal in the belt tensioner? Seems to bounce more at idle, just noticed as I put on a new belt, never really noticed with the old belt.