Thats odd Trl lghts

[truckdrivindave]

I hooked my 97 TT to move it and when I press the brakes the cab dash lights, clearance lights come on along with the trailer lights. So I turn the lights on from my rig and they all come on and the brake lights do not come on when I hit the brake pedal.

I went to my brother's house to hook to his camper after checking the 7 way on my 94 F-350 to be ok, every thing worked fine.

So back home to my TT. Since current are going to my TT lights, how do I detect the problem? I did check the 7-way connections for corrosion and the brake light wiring for corrosions, there was very little that would affect anything....short of tracking the wiring to see if there is any corrosion, chaffing or shorting since the ground is cold wet from our last snow fall. I checked all fuse in just in case for elec currents and all seem fine there. So I would guess the problem would the trailer wiring. Right?? Oh one thing I havnt done was run a seperate grounding...Would grounding have any affect on the strange light problem?

[truckdrivindave]

Since it was so weird I went out again today to check the TT light problem hooking my truck to it. It still does it when you press on the brakes. All the lights come on truck cab,dash,including brake lights. I let off the brakes they all go off. The lights are not even turned on.

Bt when I turn the lights on, all the lights are on and when press on brakes the brake lights do not come on.

I am baffled....... [img]/forums/images/%%GRAEMLIN_URL%%/confused.gif[/img]

[AlH]

Bet you have a bad ground somewhere.
Don't know what you mean about not having run a seperate ground.
Please don't tell us you did NOT run your ground through the plugs on both the trailer AND the truck. You can't depend on the connection through the ball to be reliable.

[Rick M]

Why not at least run a temporary ground straight from the trailer to the truck and see if that helps? I suspect the connection of the ground from the trailer plug to the trailer itself is the culprit.

[truckdrivindave]

Well what I meant was reground the trailer ground to see if that was the problem or do that, ground from the trailer to the truck./ aint doing it today/ watching them football games to see who will play who for the world champions/ Anxious to see if the colts could do it again.......

[DslDav]

I had the same problem with the trailer clearance lights coming on when applying the truck brakes. It was early in the morning and cold so I rushed to plug it in and jump in to go. Trailer brakes did not work and then noticed the clearance lights come on when applying the truck brakes. Well I found that even though the 7 pin plug is keyed it CAN be plugged in wrong. I think I got it 180* out. Corrected the plug insertion and all worked fine. Maybe your problem too.