Right trailer turn inop.

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Jun 27, 2020 | 08:54 PM

TxAg90

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Right trailer turn inop.

My right trailer turn and stop light quit. I have a 7 way at the bumper and in the bed. I also have the 4 way plug. No power for right turn to any of them. The book does not show a fuse for right turn.
any ideas?

Jun 27, 2020 | 09:17 PM

RV_Tech

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Not sure what truck you have, but I have never seen a circuit without a fuse for the turn signals, etc. Since it sounds like you have the other lights, you have a ground so you either have a fuse out or the feed to yourlights is disconnected maybe right at the seven pin connection behind the bumper. Corrosin is a common issue there. Did you check the pin for the lights at your seven pin with a test light or a meter? Also check the junction box on your trailer where the seven pin cord is mated to the trailer wiring. I even worked on one where a dog chewed off the wires right there at the J box. Should be an easy fix.

Steve

Jun 28, 2020 | 06:13 AM

TxAg90

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Sorry, I have a 2019 F 350, DRW, 6.7l, Lariat. Yes there are fuses for turn, but not just the right turn. I used a test light at the 7 pins.
thanks for your response.

Jun 28, 2020 | 06:46 AM

RV_Tech

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Quote:

Originally Posted by TxAg90

Sorry, I have a 2019 F 350, DRW, 6.7l, Lariat. Yes there are fuses for turn, but not just the right turn. I used a test light at the 7 pins.
thanks for your response.

So the pin for those lights at the seven pin on your truck is dead?

The fuse layout I found on the Internet for 2017-2019 SuperDuties shows fuse #72 under the hood feeds that circuit, but it also shows that same fuse feeds both sides of the trailer wiring for stop/turn. I am not sure if it just feeds a separate relay for each side. If that pin is definitely dead for one side, but the other side is good, I would suspect the seven pin right at the bumper has a problem, however it problems like this or similar to this one appear to be somewhat common place on the Internet and on FTE in the past. Maybe someone will come to this thread and verify that as I assume I can't use the diagram for my 2012.

I would also suggest running a search on this website for similar problems in the past. Hard to be more definite at a distance.

Steve

Jun 28, 2020 | 07:03 AM

TxAg90

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Yes I replaced fuse 72. Did not fix it. I will start at 7 pin at bumper. That’s what I needed to know. Thanks.

Jun 28, 2020 | 07:09 AM

RV_Tech

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Quote:

Originally Posted by TxAg90

Yes I replaced fuse 72. Did not fix it. I will start at 7 pin at bumper. That’s what I needed to know. Thanks.

I haven't had that apart for a while, but the plug used to be in two parts behind the bumper. Might want to check the Internet on that to verify. Then all you need to use is a probe to test for juice behind the plug. I would note in my Internet search that it seems like the 2017-2019 models were reporting a lot of problems with the tow circuit.

Steve