Blinkers keep blowing fuse, flashers don't work

[GravyCrockett]

Hi guys,
Been chasing down all the other problems in my new truck, but the blinkers have me baffled. When I got the truck the right blinker would work fine, but nothing from the left blinker. Switched out the turn signal mechanism in column and tried the blinkers. Left one blew the fuse immediately. Flashers don't work at all and seem to drawn down power when engaged. Other fun stuff, PO connected brake light switch to front signals, so they light up too when I stop. I don't have much experience chasing wires. Any advice on where to start would be appreciated.

[bluef250]

First, check and clean all the grounds.
Second, check and clean all the bulbs and bulb sockets.
Did you replace the column switch or just the cancel cam? I suggest the switch might be bad, as all power to blinking lights goes through the switch.
Let us know what you find.

[GravyCrockett]

I changed the whole piece, not just the cam. I suspect that the wiring was bad in the other piece, and which is why the left blinker didn't blow the fuse. As soon as there was good contact it blew the fuse. I'll check all contacts, etc, but I worry that someone did some "fixing" and that's what got me into this situation. Thanks

[68RGR]

I don't want to alarm you but problems like the ones you have described make me think of a shorted wire in a harness that has made some "unintended" connections and/or disconnections.

I had that kind of experience years ago - A wire to the right front marker light was shorted to ground at the light and it burned various wires in the harness all the way across the dash to the headlight switch. Some shorts and some opens resulted. That can cause all kinds of inexplicable problems.

If that has happened to your truck, if you look closely at the under-dash wiring, you should be able to see some evidence of it. Normally, at some point, the shorted wire will be "on the surface" of the harness bundle and you can see the burned areas.

I hope that is not the case because it can be a real, all-day pain.