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2003 Mercury Mountaineer will not start/ no communication
Posted to Technical Discussion Forum on 7/31/2016 11 Replies

I got a 2003 Mercury Mountaineer V8 4.6 that will not start or turn over. Key turns but vehicle will not start. The starter has been replaced and the battery has tested good. There is also no communication when connected to the obdII connector. I also have found out the #41 fuse continues to blow. I will replace it and it will blow when the key is turned to the start position. This is the fuse that controls the HEGO, VMV, CMS and PTEC. I have found the abbreviated acronyms Ford uses but have misplaced them. I believe this fuse controls the PCM, the 02 sensors, the evap sensors and something else. Don't quote me on that as I don't know for sure. I have looked at the wiring and everything looks okay so far. A common issue is the 02 sensors shorting out on the exhaust but that doesn't seem to be the issue. Any help would be greatly appreciated.

Kenneth Moore
Auto Pro To Call
Chapel Hill, North Carolina, USA

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