okay guys...here's my setup. '68 f100 3-speed

the backup-light switch on the end of the column, under the hood, would never stay in place. so i pulled the wires into the cab, and put them on a toggle switch. i wired a blinking LED in with the switch, so that i wouldn't forget and leave them on.
i've had it installed for months- works like a charm.

later, i added some halogen backup-lights, activated with a relay, off the original back-up light wiring. also works like a charm, and has been installed for several months. (a great mod!)

i bought a small boat, so i had to install a trailer wiring harness. no problem. when connected, all the lights on the boat work fine.

now the problem...today was the first day i actually PULLED the boat, since installing the trailer harness. as i was towing, i noticed that when i hit the brakes, my LED for the backup lights started flashing! (this does not happen when the boat is not connected).

i know that it's tough to troubleshoot someone else's home-grown wiring...but everything works beautifully...until the boat is actually connected, and i mash the brake pedal.

any help is appreciated-
thanks,
sam

 

[font color=red size=2]Check the connections first. Make sure you have good clean grounds on the pickup and the trailer. Most all the wierd problems I've had with trailer lights is because of grounds. Good luck.

Marty

 

Make sure you picked the correct wires out of the truck harness when you wired the trailer plug. If this is ok, one possibility is do you have back-up lights on the trailer? If so, it could be a grounding problem on the trailer. You might need to run a ground wire from the trailer to the truck. When you activate the lights on the trailer, the 12v could be going out to the trailer and through the bulbs, but have nowhere to go afterwards because of a poor ground, so it returns through the back-up lamps. I would think this would happen though, only if you had back-up lamps on the trailer.

 

Most Boat Trailers I've known have Special lights for submerging in the water.
I believe it's because of the special wiring for the water designated
light system that is causing the problems.



Dennis

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