How To Determine Wire Functions On A Truck Bed Camper 7-Way

Question:

my slide in camper does not have a yellow wire coming from the camper to the plug. It has all other wires for a total of six. would the blue wire be used in place of the yellow for reverse lights?

asked by: Wade

Expert Reply:

When it comes to wiring there really is no telling what the function of a wire is based on just color because manufacturers don't all follow one code. The only way to really know what the function of the wire is would be to put power to it and see what happens. That being said, the blue wire in 7-way wiring is most typically used for activating the brake assemblies on the trailer. Since a slide in camper doesn't have brakes the manufacturer could've used the blue for the reverse lights instead.

On the tow vehicle side of the 7-way the reverse light pin is in the center, so if your blue wire is ran to the center pin on the camper's 7-way it would be for your reverse lights. Whenever I'm testing functions I typically have someone sit in the driver's seat of the tow vehicle and control the light functions while I test the wires in the camper's junction box with a tester # PTW2993 and write down the functions by color.

I've attached one of our help articles below that goes over 7-way wiring to help walk you through the process. If you still have questions then let me know and I'd be happy to help.

expert reply by: Kevin C