running lights ok but no brake or turn signals

This post has drifted off topic a little bit to a "problems with connecting a running tow vehicle to a fifth wheel hooked to shore power" discussion.

I'll take up that one first. My 2005 Ram would occasionally blow the truck fuse on the 12V power to the trailer through the umbilical circuit. It seemed to coincide with running attached to both shore and truck, but not every time. I read somewhere, perhaps in owners manual, perhaps here, perhaps a technician told me, that this might happen. My newer RAM does not seem to have this problem and I have tested it inadvertently.

By the way, if the original poster says his truck lights are working and not his trailer's, then I do not see the need to check his truck fuses. As others have said, it looks like a connecting pin or umbilical cord problem to me.

DSteiner51 wrote:

laknox wrote:


"Shore power"; if you're plugged into the pedestal =and= your truck, then you start it up, you can blow fuses. I can only assume that if the pedestal breaker is OFF, this isn't likely to happen.

Lyle

Would you please explain your theory? This is so flat out wrong!

X2. There is NO connection between trailer running/turn/stop lamps and the 12v or 120v electrical systems on the trailer. There is a connection between the electric brake circuit and the trailer 12v system in the form of a 12v feed to the breakaway switch, but that should not affect running/turn/stop lamps in any way--nor should it be affected by plugging the AC cord into the pedestal. If plugging the cord into the pedestal blows fuses in the truck, there is something bad wrong.

laknox wrote:


"Shore power"; if you're plugged into the pedestal =and= your truck, then you start it up, you can blow fuses. I can only assume that if the pedestal breaker is OFF, this isn't likely to happen.

Lyle

Would you please explain your theory? This is so flat out wrong!

And on page 228 it describes a fuse box on the passenger side and shows fuses for the turn signals and brake lights.

According to the Owner's Manual on page 223 it says that the 40A fuse in position 10 of the distribution panel is for trailer towing.

i have checked both and pushed hard. I think I am going to buy a7 pin tester to check it. I have a multi meter with me so I will try that first.

When mine does that it is usually because I got in a hurry and did not get the plug in fully and seated. I go and check my plug and low and behold that is it.

I will test the plug but I did jump the pins on the plug on the cord and the lights appeared to go on. I just wish I knew what fuse. Nothing is corroded, the truck is new 9 month old. Same issue in the bumper plug too as the plug in the bed.

On my F250 the tow package fuse is in a 4x6 box just behind the air filter marked "power distribution box". Don't know where yours will be cause mine is an 2001.

Check to see if there is a panel with fuses on the left side of the dash. My truck has a panel there and you must open the door to see the panel. I had a fuse in there that blew and lost those same lights.