Attention: TDR Forum Junkies 
This keeps coming up every few months, and I figured I'd put the details in a web page: 5th Wheel & Camper Tail Light Wiring
When somebody wires an in-bed connector for a 5th wheel or slide-in camper and splices the in-bed tail light / running light connection to the truck's tail light wire - in a couple months they find their headlight switch or fuse block on the left side of the dash has burned up.
There are various symptoms, mostly their tail lights go out or flicker. This is a sure sign that the headlight switch or tail light fuse socket has been overloaded.
The truck's tail lights are powered directly off the headlight switch. The OEM headlight switch and the tail light fuse connector are not able to carry the extra current of trailer, 5th wheel, or camper lights in addition to the stock tail lights.
The factory solution to this is that the trailer tail light connection in the 7 conductor socket under the back bumper is powered by a relay in the under hood fuse/relay box. This powers the black wire with an orange stripe that is in the wire bundle running along the left frame rail, this is the one to use. The black wire with a yellow stripe is the truck's tail light wire - DO NOT use this one.
My 5th Wheel & Camper Tail Light Wiring web page describes which wire to use and a couple other suggestions. It also gives details on shop manual pages and circuit numbers on this wiring.
When somebody wires an in-bed connector for a 5th wheel or slide-in camper and splices the in-bed tail light / running light connection to the truck's tail light wire - in a couple months they find their headlight switch or fuse block on the left side of the dash has burned up.
There are various symptoms, mostly their tail lights go out or flicker. This is a sure sign that the headlight switch or tail light fuse socket has been overloaded.
The truck's tail lights are powered directly off the headlight switch. The OEM headlight switch and the tail light fuse connector are not able to carry the extra current of trailer, 5th wheel, or camper lights in addition to the stock tail lights.
The factory solution to this is that the trailer tail light connection in the 7 conductor socket under the back bumper is powered by a relay in the under hood fuse/relay box. This powers the black wire with an orange stripe that is in the wire bundle running along the left frame rail, this is the one to use. The black wire with a yellow stripe is the truck's tail light wire - DO NOT use this one.
My 5th Wheel & Camper Tail Light Wiring web page describes which wire to use and a couple other suggestions. It also gives details on shop manual pages and circuit numbers on this wiring.
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