Blowing Turn Sinal Fuses
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Staging Lane
Joined: Aug 2003
Posts: 57
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From: Norcal-East Bay
Blowing Turn Sinal Fuses turn signals are not working.. i checked the 20amp fuse to the turn signals and it was blown so i changed it out and it worked until I shut car off and restarted and put it into reverse. everytime I put in reverse it blows?? please offer thoughts
Joined: Nov 2003
Posts: 11,331
Likes: 346
From: Jacksonville, FL (originally from Toronto Canada)
The fuse you mention is actually the TURN/BU fuse. From your description, it's obvious you have a short in your backup light wiring (not the turn signals). I would check the wiring and sockets for the backup lights first to see if there is a problem with power shorting to ground. If not, then you'll have to start tracing the wiring from the fuse panel through the backup switch to the back of the car to find the short.
Joined: Nov 2003
Posts: 11,331
Likes: 346
From: Jacksonville, FL (originally from Toronto Canada)
Fuse blowing is never caused by a bad ground. It is caused by a power wire being grounded forming a short circuit - a path for electricity to flow from power to ground with no load (light bulb, motor, relay, etc.) to "slow" the flow. That makes the current flow rise to the point where it exceeds the fuse rating (or the capacity of the wire).
In this case, either the brown wire from the TURN/BU fuse to the backup switch or the light green wire from the switch to the backup lights has a cut or break in the insulation allowing the wire to contact something metal causing a short circuit. The easiest (and first) place to look is at the light green wire at or near the backup light sockets. Check for problems with the wire insulation - a pinch in the wire or a cut in the insulation. Also check the wires at the sockets to see if the two wires are shorting to each other. If you find a problem with the insulation but the wire itself is undamaged, you can wrap it with electrical tape to fix the problem. If the wire is damaged you'll have to splice in some fresh wire.
If the problem isn't at the back of the car then the next most likely place is the backup switch itself. They have been known to fail and cause power to go directly to ground instead of passing the current on to the bulbs.
In this case, either the brown wire from the TURN/BU fuse to the backup switch or the light green wire from the switch to the backup lights has a cut or break in the insulation allowing the wire to contact something metal causing a short circuit. The easiest (and first) place to look is at the light green wire at or near the backup light sockets. Check for problems with the wire insulation - a pinch in the wire or a cut in the insulation. Also check the wires at the sockets to see if the two wires are shorting to each other. If you find a problem with the insulation but the wire itself is undamaged, you can wrap it with electrical tape to fix the problem. If the wire is damaged you'll have to splice in some fresh wire.
If the problem isn't at the back of the car then the next most likely place is the backup switch itself. They have been known to fail and cause power to go directly to ground instead of passing the current on to the bulbs.
