Ignition fuse blowing 04 f150
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Ignition fuse blowing 04 f150
New guy here. I was driving down the freeway and I heard a pop from the fuse box and seconds later I was dead. I found the ignition fuse (102) blown. If I replace it it immediately blows when the key is turned on. Any help would be appreciated. I am out of warranty and walking to work.
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From: St. Louis (Out in the woods)
Need to determine exactly in which ignition switch position(s)the short occurs.
Connect an ohmmeter between the load-side terminal of fuse F102 and ground and see in which positions the meter reads zero (or close to if).
I suspect you'll eventually find you have a wiring harness fault that is shorting the START/RUN circuit to ground between the switch and the fusebox.
Edit: Well, I looked a little closer. Seems the idiots at FORD left ONE branch of the output of the IGN RUN/START not fused after the switch:
The COPS and the RFI caps are not separately fused. Based on previous experience, I'd suspect one the RFI caps has shorted. Unplug them both and see if your short circuit has gone away. If so, test them individually to see which has failed.
Steve
Connect an ohmmeter between the load-side terminal of fuse F102 and ground and see in which positions the meter reads zero (or close to if).
I suspect you'll eventually find you have a wiring harness fault that is shorting the START/RUN circuit to ground between the switch and the fusebox.
Edit: Well, I looked a little closer. Seems the idiots at FORD left ONE branch of the output of the IGN RUN/START not fused after the switch:
The COPS and the RFI caps are not separately fused. Based on previous experience, I'd suspect one the RFI caps has shorted. Unplug them both and see if your short circuit has gone away. If so, test them individually to see which has failed.
Steve
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I am sorry to sound stupid but do you happen to know the location of the RFI caps? It has been a while since I had to do electrical work on a vehicle and let's just say the cars I grew up working on were much less complicated. lol.
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Ignition fuse blowing 04 f150
Hello all, I have the same fuse blowing, I read through this thread, sounds like this could be the problem. Here's my scenario.
My 2004 F150 died coming home from work yesterday. Just had gotten on the Hy-way when all of a sudden all my gauges in the dash lossed power and the engine died. I was able to pull to the side of the road without power steering, came to a stop, put it in park, turned the key to see if the engine would crank, nothing, nada, zip. Checked the fuse panel found the ignition fuse blown 20 amp, feeds the ignition switch. All the lights work, head lights as well. I can not shift into any gear since I shifted into park. I know for a fact the battery is good. Changed the fuse, it blew again. Anyone have a wiring diagram or schematic of my truck?
Also, what do these abbreviations mean, what components are they, the COPS and the RFI caps and where would they be located? Thanks for the help, Jeff.
My 2004 F150 died coming home from work yesterday. Just had gotten on the Hy-way when all of a sudden all my gauges in the dash lossed power and the engine died. I was able to pull to the side of the road without power steering, came to a stop, put it in park, turned the key to see if the engine would crank, nothing, nada, zip. Checked the fuse panel found the ignition fuse blown 20 amp, feeds the ignition switch. All the lights work, head lights as well. I can not shift into any gear since I shifted into park. I know for a fact the battery is good. Changed the fuse, it blew again. Anyone have a wiring diagram or schematic of my truck?
Also, what do these abbreviations mean, what components are they, the COPS and the RFI caps and where would they be located? Thanks for the help, Jeff.
