When I hook up to a trailer, the light are not working properly. I had running lights but no brake or right side turn. I did something. I hit a switch for the 12volt system on my trailer and popped something. I'm taking it in for an oil change in the morning but if they don't warranty it they ain't fix'n it. Help please.
p.s. I think I checked all the fuses. Just visually. I've never seen those big square ones before.

 

First thing, post a little more information; such as, is the problem only when you are hooked up to the trailer? Or, unhooked do you now have no brake or right turn on the truck. What type of trailer is it? Are you using a 4 pin or 7 pin connection? What is your truck? If your truck brakes and right turn are out with the truck unhitched you probably had a ground fault on the trailer or crossed conductors when you hooked up. Sounds like cooked fuses on the truck. Post more info if you can

 

Trailer lights are the problem and it was the same when I hooked up to a boat today. No brake lights or right turn signal. The trailer has electric brakes and they work. Like I said, I had running lights on the trailer.

 

OK, I think I'm getting the picture. Sounds like you are using the 7 pin connector. I would use a 12 volt tester on the connector pins first. Make sure you get a good ground on the tester and then check each pin for a signal. Since this has happened with two different trailers, then it sounds like your brake and right turn pins are not getting energized. If you don't get a signal from those pins, then recheck your fuses. If your fuses are blown,then odds are your problem lies with the trailer wiring (again, either a ground fault or crossed conductors). If the fuses are good, then you have a connection problem somewhere along the conductors from the tailight harness to the 7 pin connector. Shouldn't be too hard to locate, just a little time consuming unwrapping the electrical tape.

 

Here's the schematic my Trailer dealer gave me.
(I hope you can read it, that's as big as the forum would let me make it)
make sure it's hooked up right.
You probably have some crossed wires.
if not look for a shorted wire.

 

The brake and turn signals quit working correctly on my friend's '04 Chevy. It was the turn signal unit replaced under warranty.

 

zzsdad, Run a dedicated ground to the trailer frame. I had the same problem a that fixed it.

 

Thanks for the replys. I'm thinking it's the turn signal unit. It would explain the problem hitting several circuits at once. I'll let you know in a few hours if the dealer takes care of it. If they have a new 330/600 I'll drive that too. We are holding on to my wifes vehicle as a trade for the new CTD.
I just got off the phone with the dealer. It's warranty and the part is coming. Hopefuly by 3:30 today. I'll post the exact deal when I know what it is.

Part #'s 56049019AF AND 56049681AB
That's what's on the receipt and right next to that are the two best letters to see "N/C"

 

There's also another post on this forum in the Trailer Towing side called "Inside the bed 7-Pin connector" that has some helpful info.