1994 F-150 5.8L 4WD. I noticed that the speedometer and LCD odometer stopped working (odometer blank). Truck was shifting hard. Smelled something burning in cab. Fuse 18 was blown. I replaced it, drove around the block and it was blown again. Pulled the instrument cluster and disconnected the PSOM. New fuse, drove around the block, fuse blown again. There has been no electrical/wiring work of any kind done.

What is the next most likely culprit that is blowing the fuse?
I have an ohmeter - is there some circuits I can check for a short?
Where the heck is the Electronic Shift Module? (please don't tell me it is inside the tranny)

Bruce in Austin

 

Well - I might of found the problem. I wedged myself under the dash on the driver's side and started sniffing around for the source of the burnt smell. I got up close to a module that is towards the center of the dash and got a very strong burnt smell. I removed this module, opened it up (simple plastic box and lid) and can see that it is the Airbag Control/Diagnostic Module. I know that is what it is because the chip on the PC board is marked "Ford ... Airbag". I am going to plug the PSOM back in and see if the fuse survives. I will report back.

 

Wahoo! Got lucky, it was the Airbag Module. I cobbled everything back together but left the Airbag Module out and the truck is fine. I will start another thread to ask about replacing this.

 

Were you able to get it running right? This sounds exactly like what is going on with my 94 F-150XL 2WD inline 6...Going down the road and all of a sudden I smell electrical burning and then speedo/odo go out and hard shifting...When I stick my nose behind the instrument cluster I can definitely smell something so I will look harder tomorrow. Thank you

 

Chiming in to keep this thread current. Disconnected the ABM and wahlaah, fuse stopped blowing. Speedo works and tranny shifting smoothly. Whew! I had bought what I thought was a VSS for the auto trans -turns out that my E4OD does not even have one there -it's on the differential. Returned the part. Save me a ton of aggravation. Going to put the ACM on the bench. Thank you for the suggestions