Lost tail & clearance lights

[bobwalter]

Picked up a utility trailer to tow behind my Rexhall ((1992 E350 chassis). Had to change to a 7 pin plug on motorhome. Lights ALL worked for several trips. Tail and clearance went out half way home on last trip. Where is the fuse for the tail & clearance lights? I found the box under the dash. Can almost see it. Very tight quarters. I don't think it is a fuse there... could be wrong. Is there another fuse somewhere else?? Where do I start?? What are the odds it is the switch?? How about a ground?? What order do I look first. I guess I want to know what is the most likely to the least likely. HELP..........

bOB

[subford]

Most Likely you have a bad fuse #P under the hood.
I think K is a relay but if it is a fuse it may be your problem also. If P is a relay then K is the fuse.



/

[bobwalter]

Thanks for the quick reply,Bill. We can always count on you for good information. I checked the fuses mentioned but they both were good. I am going underneath today. Going to try to find the wiring for the tail lights and follow it with a test light. Also going to check the grounds at the tail lights. Also going to try to gain access to the headlight switch and find the tail light wire there and check for power. Is there a way to get to the switch? Any more thoughts?????

[subford]

Here is a diagram and it was fuse "P" for the trailer running lamps.


/

[subford]

Note this diagram below may not be right if you have Trailer Adapter Class1 as the below diagram is for the E-series with a Trailer Adapter Class2. I do not know the Class you have.
Class1 does not have a relay and fuse "P" powers the lights without the relay as in the diagram above.


/

[garykk]

What kind of plug setup do you have on the trailer,? Is there a pigtail between the rig and trailer or is the plug hardwired to the trailer . If it all worked well for a whole I would suspect the last connections made, some of those 7 pin plugs can make poor contact, i had to "adjust" the plugs so they would make good contact..then used electrical grease on all connections.

[subford]

Are you saying that you lost tail & clearance lights on RV also or just the trailer?

[bobwalter]

I lost all tail and clearance lights on both the trailer and the motor home. The trailer lights pigtail was wired into the coach wiring by a previous owner. Always a problem trying to "fix" someone else's work. It is not on a separate circuit from the front fuse box. (trailer circuit) It is just tapped into the coach wiring in the back. I found the yellow wire (tail light) connection on the pigtail was bare (no tape) and may have shorted. The problem is that I cannot find a blown fuse. All fuses in the under hood power distribution box are good... All fuses in the under dash fuse box are good. All visible fuses have been double checked and confirmed as good with a test light and ohm meter both. The parking lights (front) work but the tail lights and all the clearance lights do not work. There must be another fuse (hidden) somewhere that is blown. Any idea where??? I am going to try to run a new wire (with an inline fuse) from a parking light (front) back to the tail light (yellow) wire and see if that works. Does that sound like a logical fix? I am not worried about the trailer lights right now. I need to first get the coach tail lights working. Then I will chase the problem with the trailer....

Thanks for the help so far. Keep the thoughts and opinions coming.

Bob

[subford]

Ford did not put clearance lights on the E-serise vans so there is not any wiring diagrams for them. Below is how Ford wired it before the builder did his thing with it.




/

[garykk]

I think you need a wiring diagram from your MH manufacturer at this point as they most likely wired the clearance lifhts etc.

[bobwalter]

That would be nice but Rexhall will not respond to any communications I send their way. I guess they don't want to be bothered with a past customer's question. Going underneath tomorrow and will run new wire. Will post follow-up.

[bobwalter]

Problem solved.... Ran a new wire with a fuse from the left front parking light to the rear of the coach. Tapped into the main taillight harness behind the rear axle. Had to go that far back in order to access wires. The harness changes colors where the builder added on to the factory wiring when they extended the chassis. This complicated matters. Thanks for all the help. Bill (Subford), you are a real treasure trove of information. I hope all you guys appreciate him. I can't thank you enough for all your help on this and other issues.

Bob

[98FPA]

Yeah I agree, Bill is a great source of information. He has helped me out too!

Everyone have a nice day.

[Donlock]

Ditto