Dead trailer plug

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Jul 28, 2010 | 03:15 PM

deercreek1

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From: Minnesota

Dead trailer plug

2005 F350 6.0. Trailer plug is dead. Checked #9 20 amp fuse under hood and #38 20 amp fuse under dash - all good. Left and right turn relays sound good. Plug in rear of truck is clean and not corroded as well as the factory plug into the trailer 7 pin plug.

I'm stumped!

Jul 28, 2010 | 04:39 PM

da-bees

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A single fuse doesn't effect all pins. If trailer lights and brakes are both dead most common cause would be at the back side of truck 7 pin. There is plug on the backside that is tricky to reconnect if it is unpluged while relocating the 7 pin. Make sure it is in all the way. If ok there,dummy a ground from truck to trailer frame. About here is where a vom is no longer optional for locating the problem. Good luck

Jul 28, 2010 | 04:52 PM

deercreek1

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From: Minnesota

My electrical engineer buddy is coming over tonight with his vom. We did check the factory Ford plug off of the 7 pin plug and all was dead. Can I just jump a ground from the 7 pin ground to the truck frame and check lights?

Jul 28, 2010 | 05:17 PM

da-bees

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The less one messes with the plug the better,as stated,if you dismantal it, it can be diffilcult to get back right. A booster cable from truck to trailer frames is a quick way to check for ground. With the vom,you can run it down easier than trial & erro. If it were me I would

and let my buddy find it when he comes over with the vom. Saaay that gives me an idea,I'll be right back.

Jul 28, 2010 | 05:33 PM

deercreek1

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From: Minnesota

Problem is I think he is at the pub right now. I did find the wiring schematic for the trailer fuse box under the hood. We'll see......

Jul 28, 2010 | 07:20 PM

sandmanf250

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i love being at the pub.

Jul 29, 2010 | 08:25 AM

deercreek1

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From: Minnesota

Yep, he showed smelling like he had fun. We checked the relays, fuses, confirmed power going out of the fuse block. Went back to check the trailer plug again and now it works. This might really **** me off.