Trailer Lights

[nwohiochevyguy]

OK I pulled for the first time with my 2005 2500HD CCSB 4x4 and I noticed that my interior lights on my trailer do not come on.

Is this simply the case of inserting a fuse in the fuse box?

Thanks in advance.

[blksmok]

OK I pulled for the first time with my 2005 2500HD CCSB 4x4 and I noticed that my interior lights on my trailer do not come on.

Is this simply the case of inserting a fuse in the fuse box?

Thanks in advance.

"interior lights on my trailer"?

The trailer interior lights run off the trailer battery. There is a fuse in the engine bay fuse box that needs to be inserted to allow the truck to charge the trailer battery while it's connected. Is this what you are refering to?

Also, many trailers have a battery disconnect to prevent the battery from being drained while in storage. You'll need to "connect" the disconnect in order to power interior lights on the trailer.

I'm not sure if this is what you are talking about or not though, so I hope this helps...

[Darius6t9]

Mine don't run off my battery on the trailer. I had the same problem when I first bought mine. But when I wiggles the RV plug around, they would flicker. Found out that a couple of wires in the connector were loose. Tried to tighten them and the screws were stripped. So I to some pliers and squished them a little bit and has worked great since. Don't know if this might have happened to you. But that was my experience.

[blksmok]

Exterior trailer lights work off the plug attached to the truck.

Interior trailer lights work off the trailer battery.

Was the OP talking about interior or exterior? That's where I'm confused...

[Darius6t9]

He said interior lights. As for the battery thing. There is one on my trailer. But the only thing it is hooked up to is the brake system in case the trailer detaches from the truck. I traced the wires once to find out where they all went. But that is on MY trailer. That and if you unhook it from the truck the lights go out.

[minisub]

I was originally thinking about the same fuse that Dave is referring to, battery or not. If that is in place, I would also recommend disconnecting the harness from the socket on the truck side, blowing it out, putting some dielectric grease on it, saying some favorite phrase, tossing salt over your shoulder, rubbing a rabbit's foot and then reconnecting it.

Had I thought of that first last fall when I went to Long Island to get a boat, I would have 4 hours of my life back and not be the proud owner of a cheap multi-meter that I don't need...):h

[nwohiochevyguy]

It is the interior lights of the trailer. On my 1500 there was a fuse I had to insert in the fuse box to make that circuit active in the trailer harness.

Like someone else already stated the battery on my trailer is only for the break away brake system.

I did just look in the manual and it makes no mention of this. I guess I will have to wait until I get home and dig alittle deeper with a volt meter.

On my other truck these lights were the only thing that were powered by this "added" fuse. I don't remember where and what it was, looked in fuse box and did not see any open slots.

FWIW: everything else works for the trailer, brakes, running lights, etc. etc.

[nwohiochevyguy]

OK, it was getting to me so I had to figure it out.

With alittle internet searching and another trip out to the truck I did figure it out.

This Pin on the trailer harness (12V power) is powered by the circuit that is fused on stud#1 in the underhood fuse box. I found that 40A "maxifuse" blown and will replace it tomorrow. This is the "Aux" or yellow wire in the harness.

For those who were trying to help. Thanks.

Now we all know.

[TheStepChild]

if you tow a lot and/or different trailers do yourself a favor and bypass the factory trailer battery charge and running lights line. for some reason they blow often.

[nwohiochevyguy]

I did run a switched power supply on my last truck for the trailer, but having it all in one connection would be so nice. I will probably give it a try for awhile, if it don't work or blows the fuse often I'll put the charging / power circuit back on he truck.

thanks