Join Date: Dec 2008
Location: norman, ok
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If the fuse doesnt blow instantly when using the turn signals or brake lamps then its going to be a little difficult to trace. Since you mentioned LED tail lights I would start thinking about those first. Its possible that you pinched the wiring behind the lenses when mounting up the tail lights. You might try using the left or right turn signals one at a time and at least see if your problem can be trace to a particular side.
What you might try to do is....Since the fuse powers multiple circuits its rated at 20amps. You can down rate that fuse to try to pinpoint the circuit that blowing it. Turn signal bulbs alone dont need but a couple amps so maybe downgrade to a 10amp or 15amp fuse, then turn on the turn signals one side at a time and see if that shows anything.
Keep in mind that fuse also is for the brake lamps along with the flasher relay for the turn sigs. If you had a relay or switch problem I would suspect the lights would want to stay on, not blow a fuse. I have seen a few issues with the brake lamp switch wires rubbing things since the wire moves with the pedal it can rubb and ground out on the pedal bracket or something else near the switch. Unplug the brake lamp switch and check the connector for heat damage too. Brake lamp switch is mounted to the brake pedal above pad and where master cyl hooks up
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94 F250 IDI turbo, auto 2wd.. ATS housing, 3" down, 4" exh, guages. 104k miles got totalled by a damn mustang (parts now).
98 12v, 4x4 quad cab. auto with BD T/C & V/B, Banks Big head, Exh brake, AFC modded, 16.5ish*, KDP gone, 60lb springs, 4K-GSK, BHAF, pyro, trans, and boost guages. 4" straight pipe,
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