Two fuses keep blowing simultaneously
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Two fuses keep blowing simultaneously
1986 Ford F-15 XLT lariat
Brake lights and turned signals stopped working and two fuses blew.
Replaced the turn signal switch thinking this may be the issue. Prior to this, the turn signal stem you would have to hold down to keep the flashers on. The signal stem worked appropriately for about 10 turns of the wheel but then if you turned the signals on, they would stay on and you would have to manually turn off. The exact opposite of what the issue was before. However, the lights began working again for about four days until the fuses blew again while driving.
Also replaced the trailer harness wiring today and replaced the fuses yet again. I don’t believe this is going to fix the problem long-term and just wanted to see if you had any ideas why both fuses would be blowing at the same time to try and pinpoint the issue?
Brake lights and turned signals stopped working and two fuses blew.
Replaced the turn signal switch thinking this may be the issue. Prior to this, the turn signal stem you would have to hold down to keep the flashers on. The signal stem worked appropriately for about 10 turns of the wheel but then if you turned the signals on, they would stay on and you would have to manually turn off. The exact opposite of what the issue was before. However, the lights began working again for about four days until the fuses blew again while driving.
Also replaced the trailer harness wiring today and replaced the fuses yet again. I don’t believe this is going to fix the problem long-term and just wanted to see if you had any ideas why both fuses would be blowing at the same time to try and pinpoint the issue?
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Joined: Jan 2001
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From: Virginia
Which two fuses are blowing? The brake and the signal flasher fuse? If so, those fuses have in common the wiring to the rear. Your clean up at the trailer plug may indeed fix it. If not, inspect the wiring to the rear carefully all the way up the frame rail. The rear turns and the rear brakes are the same wires and the same bulbs in the rear..
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Joined: Nov 2015
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From: Angier, NC
I was going to say check or just replace the light bulbs as they have caused some crazy things to happen.
Not knowing where the trailer lights tie in to the trucks harness but on my truck it Tee's in between the frame & tail light harness.
I can unplug the trailer harness and plug the tail lights back in to test that part.
Or unplug the tail lights also and test the frame harness.
You can also unplug the frame harness from the main harness under the brake booster and that would test the main harness.
Now you cant really drive with out rear lights but you can shake / move the harnesses to see if that causes the fuse to blow.
Dave ----
Not knowing where the trailer lights tie in to the trucks harness but on my truck it Tee's in between the frame & tail light harness.
I can unplug the trailer harness and plug the tail lights back in to test that part.
Or unplug the tail lights also and test the frame harness.
You can also unplug the frame harness from the main harness under the brake booster and that would test the main harness.
Now you cant really drive with out rear lights but you can shake / move the harnesses to see if that causes the fuse to blow.
Dave ----
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