Wiring For Backup Lights On Toy Hauler

[1L243]

I am trying to figure out the wiring on the 7 pin connector for my 1999 Ford Super Duty. I want to use the Ramp Lights on the Toy Hauler as backup lights when I put the truck in reverse. I have read that the center pin is used for backup lights. I have tested the center pin (truck side) and get no power when trucks backup lights are on. I can't find any continuity from the center pin to the wires comming out of the 7 pin connector even though I have seven wires? I have white,blue, brown w/white stripe, yellow, green, black w/green stripe and orange? Any idea of which color wire is used for the center posistion? I know on the trailer side it's yellow but not on the truck side...

[1L243]

Update. I removed the 7 pin connector and pigtail from the truck. Peeled back all the electrical tape and inspected the connections. I found that the black w/green wire was never connected. It was taped back against the wire harness. I don't know why they would go through that when they just could have connected the wire. The truck has the towing pkg and was wired from the factory. I connected the black w/green stripe wire to the center pin on the 7 pin connector and pluged it back into the trucks harness. Tested for reverse or backup light and it works.. Now, adding a relay and running wire to the back of the trailer and connecting to ramp lights will be the next step.

Thanks for all the feed back...

[BurbMan]

Not a big deal...not all trucks have the center pin connected. All you need to do is find the wire going to the center pin and tap into one of the reverse lights on the truck. The circuit won't carry the current you need for the ramp lights (possibly if they are LEDs) so you need to use a relay with the center pin wire the relay trigger.

GM had connected my center pin to reverse at the factory, so all I did was add a relay to power the lights from the trailer batteries and run wiring back to the lights.

[1L243]

I think I will have to pull the 7 pin connector apart and see if center pin is wired. When I pull the plug from the trucks wire harness and test the contacts with a continuity tester and the center pin I get nothing...

[RoyB]

I would also check the owners manual for the truck and see if there may be a FUSE and RELAY associated with trailer/tow backup lights.

I have never tested for back-up lights power on my 2010 FORD truck but did have to install a FUSE and a RELAY in the main fuse panel before I could get TRAILER TOW 12VDC power on BLADE 4 of the trailer connector. Maybe a quick call to the FORD SERVICE MANAGER will get some answers for you...

Also ETRAILER has alot of info on connecting up trailer connectors etc. Might scan through all of that to see if anything helps.

ALso keep in mind BACKUP LIGHTS on your trailer will fall under DOT RULES for safety lights. They may have issues with what you are planning to do when it comes to SAFETY INSPECTION time.

I got busted once for adding BACK-UP lights mounted under the rear bumper to my OFF-ROAD POPUP trailer. DOT wanted those to come ON only when I was in reverse with the truck which I had them coming ON with a manual switch in the trailer. I also did not have DOT APPROVED back-up lights lens - no DOT NUMBER etched into the lens.. I had to quickly remove all of this before I could pass my safety inspection.

Roy Ken

[Brodie3Az]

You may need to disassemble the tow vehicle connector to see if the center pin is connected to the vehicle wires.

Keep in mind that depending upon the type of ramp lights on your trailer, your tow vehicle wiring may or may not be able to handle the load. You may want to use a relay which would permit you to use the normal trailer electrical wiring to power the ramp lights.