Running/tail Lights Not Working

We have a 2004 3326. The running and tail lights are not working, the brake lights and turn signals are both fine. Fuses and bulbs are all OK. Any ideas on where the problem might be?

Thanks,

Robert L
SE Michigan

Robert,

Check the connectors on the end of the 7 wire cable in the outside fridge compartment.

[Joe]

Originally Posted by beahold

We have a 2004 3326. The running and tail lights are not working, the brake lights and turn signals are both fine. Fuses and bulbs are all OK. Any ideas on where the problem might be?

Thanks,

Robert L
SE Michigan

Here is a way to check it out. Make yourself a testing tool by getting a 8 to 10 inch piece of number 12 or 14 insulated solid electrical wire, strip about 3/4 inch of the insulation off each end and then bend the wire into a 'U' shape.

Look at the 7 pin plug on your trailer. Hold it so that the locating bar is at the top, in the 12 o'clock position. The 12 volt supply socket is at 11 o'clock.
The running lights socket is at 1 o'clock. The right-turn socket is at 9 o'clock and the left turn socket is at 3 o'clock.

Just for verification, push the U-shaped tester into the 11 and 9 o'clock sockets. Check your right turn lights to see that they are working.
If that checks, push the tester into the 1 and 11 o'clock sockets. If everything is OK the running lights will be ON. If they are not on, you'll need a 12 volt meter, test light or test buzzer, or maybe just luck to find the problem. In my 2720SL the cable from the trailer plug runs to an area near the refrigerator access door. Under the trailer at that point are connections where the cables from the top back and top front connect to the trailer plug cable. These are 'push together' connectors and are susceptible to intermittent connections due to corrosion, especially if you have been in wet weather. Try wiggling the connections to see if the lights come on. If so, pull the connector apart (they fit tight so you might need 2 pairs of pliers), clean both ends and apply some anti-corrosion grease to the connectors before reconnecting them. Auto parts stores will have a small tube of the anti-corrosion grease, it may be labeled battery corrosion compound.
An additional tip; remember that there are running lights on both the front and back shells. Check to see if the lights are out on both shells or only one. That will simplify your search.
In the unlikely event that the lights are OK when you make the 11 and 1 o'clock connection, you have a problem in your Tow Vehicle.
I hope this helps.

When I used to work in an RV repair shop, about 80% of the lighting problems were with the Bargeman plug. Most of the time it was very simple - clean the prongs on the plug and the lights would work. Occasionally it would be the wiring to the plug from the vehicle and once in a great while it would be in the trailer wiring. Corrosion on the plug elements will kill a circuit in a hurry - shine them up wit a piece of fine sand paper or a fingernail emery board trimmed to fit the slots. If nothing else helps, check the wiring to the plug - those of us who are cursed with cold winters have a problem with ice building up on exposed wiring and the weight can make the connections come loose. If the wiring was spliced into the TV wiring, the phony little 3M connectors are a source of problems many times. As Joe mentioned above, test your trailer lights with a wire. Test your TV plug with a test light with the wire clipped to a known good ground. Since the other lights work, the ground isn't a suspect - if none worked, the ground would be the first place to look.

Thanks to everyone. We figured it out today. We hooked up to a different tow vehicle and everything started working again. Must have been something wrong in the other tow vehicle.

Thanks,

Robert