trailer wiring problem

[Toms57]

Take a small screwdriver and spread all of the posts in the tow vehicle side of the connector to insure a good connection inside. Also you could use a set of jumper cables between the truck frame and the trailer frame to insure a good ground. This will help isolate the problem.
On the lights that you have, are you sure that the white is the ground wire?

Tom

[Eric_H_E]

Check the bulbs. Are they the 2 filament type? They may be installed backwards. Or they may be the wrong bulbs all together.

Good luck.

[336muffin]

The red and brown wire?

[Red man]

I use a cheap tool from the parts store that has helped me often .It looks like a screw driver with a very shrap point on the end and wire coming out of the handle end, (which is hooked to ground .Clip it to ground and push the sharp point into the blue wire and have someone push brake pedal (a stick can also by used).If a good connection is made the handle of the tool will grow bright.
Even though you have replaced the wires , does not mean the connectors are making a strong connection. This tool will allow you to clip onto the ground and check points anywhere in the system. You can also check the strenght of ground wires by clipping onto a good know12vdc source(battery terminal positive) and pushing the sharp point into ground wires at various points.I find this helpful at the back of connectors too.
GOOD LUCK

[Billieg]

This may be a long shot but you didn't say what tow truck you have. My Ford has the towing package and under the hood are 2 relays. I had all kinds of problems with my lights until I changed out the relays. Took forever to figure it out.

[vidaliaman]

good idea, this will eliminate some things, i will report

thanks again
dave
gowen mi