brakes and turn signals don't work on boat trailer
 

I have a bass boat with surge brakes. I have power only and no brake lights or turn signals. I have traced it back to the truck. It is a truck problem. I get only running light power from the pigtail on the truck. I can't locate a bad fuse by using my manual. Help!

UncleRay

You've checked it at the plug on the hitch with a multi-meter or a test light? Sometimes the sockets get dirty and need a good douche with an electrical spray cleaner.

Check the relays under the hood. There are two or three that are specifically for the trailer.

I don't think that is it.
 

I cleaned all female and male connections. But, the main clue is that only one of the metal flanges on the FordMoCo female connector has a positive for current. That connector is standard equipment on my F150 and before any after market adapter or trailer based connector is attached. So, the problem seems to be truck related.

Ray

Kevin,

How can I tell if a relay is bad? Is the relay one of the square fuse types or the black solid electronics? I guess I could use a meter on them. But, which ones? Schematic helps some.

Ray

And you checked the relay in the engine compartment?

I am not that savvy about the relays. What and where? Any help would be appreciated. I don't know what I am looking for and am afraid to mess with anything that I don't have a clue about.

Ray

The relay/fuse panel is in the engine compartment. The lid comes off and will show you the relays. Relays 37 and 38 are for the trailer tow park and turn signals.

Kevin,

I'll check relays 37 and 38 for trailer late tomorrow. I have to go to St. Louis to talk to Cardiologist tomorrow. That will take all day.

Ray