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Old 05-18-2017, 09:03 PM   #1
 
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Default Turn signal fuze blowing
I need some help here, the turn signals on my truck were working fine then it blew a fuze. I put a new one in and as soon as i turn the key over it blowes it again without activating and of the turn signals. I thought it might be somthing in the switch since i just put a new cam in it so i unpluged it. It did the same thing. Flashers work fine. Any ideas on where to start? Wiring is my weakness lol

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Old 05-19-2017, 01:55 AM   #2
 
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There are two circuits supplied by that fuse - the T/S lights and the B/U lights.

Isolate the circuit with the short by pulling the T/S flasher.

If the fuse doesn't blow - with the T/S flasher pulled, the short is in directional lighting. And because it is blowing without operating the blinkers, the short is most likely in the feed from the flasher/fuse block to the switch.

If the fuse continues to blow - even with the flasher out...inspect the wiring to your B/U lamps switch. The location of that switch depends on transmission type. A/T is in the neutral safety switch at the bottom of the steering column. If you have a M/T, it is probably mounted on the casing.
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Old 05-19-2017, 10:09 AM   #3
 
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Best way to troubleshoot steady or intermittent 12V short is via insertion of horn in place of fuse w/ male spade connectors. With that and a schematic, start isolating as stated above, you will have it figured out soon.

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Old 05-19-2017, 01:33 PM   #4
 
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Originally Posted by jetman View Post
Best way to troubleshoot steady or intermittent 12V short is via insertion of horn in place of fuse w/ male spade connectors. With that and a schematic, start isolating as stated above, you will have it figured out soon.
Or become thoroughly annoyed. You can use a 12v lamp instead of a horn if you prefer a quieter method. The only downfall is you need to see it. long wires allow it to be located in a visible area.
Another option would be a buzzer like the one for the door or key-in.


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Old 05-19-2017, 07:11 PM   #5
 
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Originally Posted by Georgeb View Post
Or become thoroughly annoyed. You can use a 12v lamp instead of a horn if you prefer a quieter method. The only downfall is you need to see it. long wires allow it to be located in a visible area.
Another option would be a buzzer like the one for the door or key-in.
Rag should be stuffed in horn to keep sanity. Watching a lamp while keeping an eye on wires as they are manipulated is difficult. Low impedance load, as opposed to piezoelectric key-in buzzers, works well in diagnosing intermittent issues.
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