Case #85: Five Equals Four with a Diode OR

June 05, 2006

Trailer rental firms insist that tow vehicles provide operating lights - turn, tail and brake lights for every towed vehicle rented. Easy to do if the tow vehicle is wired that way, but a pain if it has separate turn and stop lamp circuits. John's solution is a pair of diodes, some quick disconnects and an inexpensive wiring harness. He used Schottky diodes for low- voltage drop, rated 3A to handle 36W of trailer lights. He then threw in a few quick splice connects for the rear tail light wires and the mate to the trailer's 4-Way Flat and was set quicker than he could say "You haul!" Oh, yeah - be sure the vehicle and tow hitch can handle the trailer, cargo and tongue weight.

Trailer Lights Hookup Kit Parts List
Amt Part Description Allied Part #
2 3A Schottky diode 273-0620
4 Quick splice connector 534-1240
Additional parts required: Champion Trailer # 4378 car side trunk connector

This Gadget Freak is undergoing an update. Please revisit this link soon for the full instructions.

For parts information, call (800) 433-5700, or go to

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