Electrical problem with back-up lights

**mbrownin** · 06-01-2010, 03:09 PM

Within the last week, the 20A TURN/BKUP LTS fuse has blown twice. The problem is somewhere in the back-up light circuit. With a new fuse, the turn signals work fine. As soon as I put it in reverse (M6), the fuse blows. Right now, I have a 40A fuse installed. It no longer blows the fuse, but the back-up lights don't work, and the battery gauge takes a nose dive when I put it in reverse, and the fuse gets rather hot.

Where is the most likely place to look to troubleshoot this?

**SteveCZ28** · 06-01-2010, 04:25 PM

i would take the taillights out, and inspect your wiring. maybe your reverse light on one side or the other is rubbing the tail light housing and grounding out on the body panel in there...and make sure the wiring is still somewhat loose, and doesnt feel like its getting caught on anything

**mbrownin** · 06-01-2010, 04:49 PM

Yeah, I kinda figured that would be the case. It sucks because I have an amp rack mounted where you need to get to the rear lights. Guess it's coming off

**mbrownin** · 06-04-2010, 08:12 AM

Update: I've determined that the problem is NOT in the immediate taillight area. If I disconnect the terminal that feeds the lights in the left rear corner of the vehicle, I can supply 12v power to the backup-light circuit on the taillight side, and the lights work fine. Update#2: I've now isolated the wire on the drivers side just ahead of the front seat, and it's ok from there back. So, the short is somewhere between, I guess, the backup switch on the tranny and where I last isolated the wire. Anybody know where the switch is that is activated when the tranny is put in reverse? I'm gonna find it eventually.

**GatorSS** · 12-25-2014, 02:15 PM

Any update to this? I am havng the same problem. Every time I put the shifter to the reverse position, that fuse blows. Where is the switch that activates when shifter is put in reverse?