Troubleshooting Trailer Pulling Too Much Amperage Blowing Fuses on 2012 GMC Sierra

Updated 10/24/2016 | Published 10/22/2016

Products Featured in This Question

ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit

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$198.36

ModuLite Installation Wiring Kit

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$19.52

Question:

I have a 2012 GMC Sierra with the factory heavy duty towing package built in. That includes a 7 blade trailer power cable and several dedicated trailer function fuses. I have refurbished a 1996 Fleetwood Prowler and in doing so I changed out the running lights to double .27 amp lamps ending up with 11 lights and 22 lamps. I also added 2 Optronics single bulb side marker/signal lights which I am sure draw more than an amp each. My sierra is equipped with a 10 amp trailer running light fuse which I have blown. I am an amature with trailers and did not realize the problem I caused by doubling up bulbs and adding the large OPtronics. Do you have a simple 7 point Trailer Light Power Module or a 4 pt that will work to transfer the load from the running light circuit to direct battery draw that will handle my marker light set up?

asked by: Larry B

Expert Reply:

The best option to avoid blowing fuses on your 2012 GMC Sierra is the Tekonsha ZCI Circuit Protected Vehicle Wiring Harness # 119250KIT. This harness provides a maximum 16 amps for the tail light and 4.2 amps per stop and turn signal circuit.

This harness installs on the truck and you will use the tail light wires from the factory 7-way to connect to the input wires on the harness. Then run the out put wires to the tail light wires on your 7-way.

There's also an optional installation kit, # 118151 to make it easier to run wiring to your truck's battery.

expert reply by: Charles S