This 1994 Ford F150 was towed in with a no run condition. The customer told me that he was driving along and started smelling something burning. The next thing he knew there was smoke under the driver’s side of the dash and the engine stopped running. I have seen this before, so I stuck my head under the dash near the parking brake assembly and checked for the burnt smell. Sure enough, the sweet smell of burnt electronics. the computer had expired.
The computer is a little difficult to remove. First loosen the 10 mm headed bolt on the center of the PCM harness connector.
Next I removed the upper and lower 11 mm nuts that hold the retaining plate in place. Notice I used a swivel and long extension.
The cavity with the PCM removed. It is not quite as easy as just pulling the PCM out though.
The inner fender panel has to be loosened up so that the plastic panel can be flexed enough with a pry bar to allow the PCM to be removed. There are several screws along the curved edge of the plastic panel that have to be removed and one underneath. After that a pry bar can be inserted between the plastic inner panel and the steel fender edge. I did not have a good feeling about the chrome trim
So I removed the phillips headed screws that held that on.
And removed the trim from the fender.
I would recommend taking you time and being careful so that you do not damage the paint or the fender with careless or excessive force. Free at last.
Now with the PCM out of the truck, I could really smell the burnt electronics emanating from the unit.
There are two torx screw that hold the sheet metal cover in place. One on either side.
I think it is safe to say this PCM is toast.
I have seen about a dozen of these over the past 4 or 5 years and to my knowledge it is an internal failure. I have seen nothing in the engine or transmission system to be causing this kind of failure.