Trailer lights not operating properly

I have a new (<60 days) 3023. I have no brake light on the right side of the trailer. The directional signal works fine. The directional signals and the brakes operate on different connectors from the tow vehicle. I tested the wires where they come into the trailer below the refrigerator and the brake signal has already been lost at that point. The signals for the left directional and brakes work okay at that point. Somewhere between the trailer plug and that point, the signals must be combined since only one wire leads to the rear lights. Does anyone know how the signals are combined and where I might find my problem?
My dealer is totally helpless with ANY problem I have encountered. All they seem good for is to order replacement warranty items from the factory. At least they say that they have ordered them. I haven't seen any parts yet.

[Bill]

Something isn't coming together in my mind. The combining you refer to is done in the tow vehicle, not in the TM.

The standard connections for the Bargman 7-pin connector can be seen at http://home.maine.rr.com/billjeffrey...geman%20TM.jpg.

As you can see, the brake light and directional light functions are combined before they enter the TM. The Brown terminal is
right brake light + right blinker light. The Red terminal is the left brake light + left blinker light.

The other terminals are for +12vdc, ground, backup lights, marker lights, and trailer electric brakes.

So, if both blinkers work, that means that the Brown and Red wires are good, all the way through. If the right brake light doesn't work, that has to mean that the tow vehicle is not connecting the brake light signal to the Brown wire. The problem is in the tow vehicle, not the TM.

You can confirm this by measuring the voltages right at the trailer connector. When the connector halves are mated, you can't get a meter probe into it, of course, but here is a trick I developed a while ago to get around that. Remember, we are dealing with only 12 volts here, so you can't get a shock. Take a 2" square piece of aluminum foil. Fold it in half. Fold it again, parallel to the first fold. Then fold it yet again, still parallel to the first fold. You now have an 8-layer thick strip of foil which is 1/4" wide by 2" long. Pull the trailer plug out of the tow vehicle socket. On the plug, identify the pin that you want to measure (in this case, the right brake/turn), and push the end of the foil strip into the plug opening for this pin. Carefully fold the protruding end of the foil strip back against the outside of the plug, and push the plug into the socket. The end of the foil strip will stick out far enough for you to put a meter probe on it. Put the black lead of the meter on any handy bare metal ground.

My guess is that under the sink, you are looking at the trailer electric brake line, but thinking you are looking at the brake light line. The terminology is confusing, but the functions are not the same, of course.

Let us know what you find.

Bill

False Alarm! The more I thought about it, the more I came to the same conclusion as Bill. So I checked the fuse box and sure enough, the 2002 Silverado has a fuse for both Trailer Left Dir and Trailer Right Dir. The right was blown.
Now, my problem was why did the directional signal work but not the brake light? ? ? ? I did a little more investigating and found that someone had put a jumper at the rear of the truck from the truck light harness to the trailer harness for the right directional signal. It all made sense then. Sorry! ! !

[dlajoie]

I don't have an answer for the problems discussed in this thread but rather an additional question. The right rear bulbs on my 2003 2720SL are dimmer than the left rear bulbs. When I uncovered the TM after last winter, I noticed the right rear taillight bulbs were out. So I bought replacement bulbs. I'm quite sure they were the right ones to exactly replace those that didn't work. Are there any electricians out there who can further diagnose this problem?

[Bill]

Two things come to mind.

1. The inside of the socket - particularly the little contact button - have gotten a bit oxidized or corroded. Rub the button and the inside of the brass sleeve with a pencil eraser - one of the old gritty typewriter erasers is even better, but no one has those any more.

2. The ground connection (from the sleeve part of the socket to the frame) has gotten a bit corroded. It's been a while since I've had mine open, so I don't recall exactly how it is connected, but look for a short wire screwed or riveted to the trailer frame, and clean the connection if necessary.

Bill

[dlajoie]

Many thanks to Bill for the common sense answer. The fact that the answer can be shared with the rest of TrailManor owners is what makes this site the very best!