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I have no stop/signal lights to my trailer plug. I do have running lights and a good ground. Have check all fuses under hood and in cab, which included checking fuse with Ohm meter and making sure I had power to the fuse terminal plug. Checked wires at trailer plug and harness up into engine compartment. I do not know where they originate. I need to trace the Yellow and the Green wires from trailer plug back to source. All truck lights work correctly.
Any help would be appreciated.
Generally speaking, newer trucks in general have a take-off in the wiring harness somewhere near the rear lights for running lights, stop/signals, and a ground. Where exactly it is on Fords I have not dug into since mine works just fine
Generally speaking, newer trucks in general have a take-off in the wiring harness somewhere near the rear lights for running lights, stop/signals, and a ground. Where exactly it is on Fords I have not dug into since mine works just fine
This isn't accurate. Fords, going back at least as far as the mid 90's, maybe earlier, have dedicated trailer towing circuits built into the trucks wiring. They consist of fuses, usually under the hood, and dedicated relays, also usually under the hood. I discovered this when we had trailer light issues on my Dad's '96. One of the fuses was blown, under the hood.
In the OP's case, both the left and right stop/turn signals are out (I know I'm assuming that from what he said). This would lead me to think it was a fuse, because many models years used a single fuse for both left and right stop/signal, relays don't usually go bad, and it would seem unlikely that two relay's would go bad at once. But, since he's checked the fuses well, the only thing left are the relay's. I don't think relay's are well covered in the owner's manual. That is something you might have to go to a service manual for.
yeh, need the yr/model so we can help more.. but if you've traced the harness all the way back to the engine bay, then its almost surely a fuse or relay..
Sorry about that. It is a 1997 ford F150 4 whl dr extended cab short box. 4.6 engine. I thought of relays but didn't see any related in the owners manual. Would it be combined with something else?
First of all, I'll point out that you're posting about an F-150 in the Super Duty forum. You might get a better response in an F-150 forum. However, trailer light circuits should be pretty much the same between the two.
So... Yeah, the owner's manual is pretty lean on information about the relays and the locations and stuff. On the super duties, they are usually in either the power distribution box, or one of the auxiliary relay boxes under the hood. Problem is, they moved them around a lot between years, and I imagine between models.
So, I would recommend some sort of service manual. Some guys get good buys on genuine Ford DVD or paper service manuals on E-Bay. You'd just have to search. They are model and year specific.
I use an online service at ALLDATAdiy.com :: Leading Source of Diagnostic and Repair Information. For my 2004, it's pretty good. For Dad's '96, it's pretty sparse. For the two Toyota's and the Honda I've used them for, they suck. It's about $25 for the first one year subscription. Since the value of the data seems to be a crap shoot, it might be a gamble but if it has what you need it's a pretty cheap way to start out.
Your other option would be to see if you can find someone in the F-150 forum who already knows this stuff or has the manual.
I don't know about the F150, but I had the exact same problem on my 2002 F250 recently. As already stated, the super duty has a separate circuit for the trailer/towing lights, and in my case it ended up being the flasher that is located under the hood. On my truck the box was located on the left side close to the firewall.