I purchased a 1997 F-150 3dr with 4.2 v6 2wd recently and was enjoying it until it died on me. It will turn over but will not crank. I tried replacindg the coil and crank sensor ,but it still only turns over. we could not get any codes only "not communicating". I was told all signs pointed to replacing the ecu (located in firewall at passenger side kick panel). I am waiting to recieve new ecu but have to have it "flashed". I am wondering if anyone knws the location of the fuse or circuit breaker for the ecu, or has any other suggestions to fix. It isn't getting fire or fuel. THNX.

 

I am not positive ecu (engine control unit?) is the correct name for the computer unit that I have ordered. I hope u can get a sense of it from where it is located. 3254 was the identifing number I used when ordering. I realize these are vehicle specific according to axle ratio etc.Advance calls it core engine control.

 

I would recommend repalcing the crank sensor first. Thats alot cheaper if you are going to throw parts at it and dosent have to be flashed.