bubba7700

Just bought a 2000 f250 7.3. Appears it has an aftermarket 7-way plug. Lights on my trailer dont work. Brake lights and turn signals work though. The fuses are all ok, triple checked them. Any ideas?

360ci

Alright. I gotta ask. Do your lights work on the trailer or not? I ask because you mentioned "Lights on my trailer dont work. Brake lights and turn signals work though.".

If what you mentioned in the second sentence that I quoted is true, turn the lights of the F250 'on' and see if the running lights work. If the running lights on the trailer work, then having brake lights and turn signals is all you need. If you require a brake controller for the trailer, have a look under the dash to make sure the connector hasn't been kicked or mangled.

If you don't need trailer brakes, utilizing a 7 to 4 pin connector is the way to go. I only need 4 pin now for my smaller trailers as they're rather light and require no brakes. If the trailer has surge brakes, then you can still use a 4 pin connector.

If you were right in your post the first time when you mentioned none of the lights on the trailer work, then I would suspect either a bad ground, or a poor connection. You can Ohm out most trailer wiring issues, however you'll almost always need a second set of hands.

Another test if you are using a brake controller is to get it up to speed on a dead but paved road and check stopping distances by overriding the trailer brake controller to slow the vehicle rather than the service brakes of the tow vehicle.

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'00 Durango R/T 360ci 290hp (modded); 138,500m
'06 Pontiac G6 GT 3.5L 220hp; 44,000m
'12 Chrysler 200 Limited 3.6L 283hp; 13,000m
'99 Taurus 3.0L 2V Vulcan 145hp; 154,300m - Traded
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