Troubleshooting Left Turn Signal on 7-way Installed in Bed of 2011 Chevy Silverado 3500

Question:

Hello: I have a 2011 chev 3500 long bed dually, Previous owner had a 5 pin connector installed at the front of the box for a slide in camper and I installed a 7 pin in the rear of the box for my 5th wheel. All worked well but now have lost the left turn signal/brake to my trailer. Signals/brake lights work fine on the truck but have no left turn on either the 5 pin or 7 pin connectors. Have checked fuses and not sure where to go next.

asked by: Arlo G

Helpful Expert Reply:

How is the 7-way in your truck bed installed? Is it a T-connection like the # PK11893-11932 you referenced?

If so, unplug the fifth wheel connector portion of it entirely and plug the factory US car connector into the rear of the 7-way on the rear bumper. Then, check the pin in the 9:00 position while the left turn signal is activated. If you get signal on that pin, there is a problem with the T-connection for the fifth wheel. You can check the pin-out on the connector in the truck bed (see diagram) to make sure that the red wire has not come loose.

If you do not show a signal on that pin, something likely came loose where the 5-pin connector you described was tapped in to the tow package wiring. I would recommend tracing the wiring for that 5 pin, to make sure nothing has come loose.