Exterior Lights Not Working

[Kevin A]

Our Silver Cloud has 4 exterior lights: one each front and back and one on each side. The rear light and door-side light work fine. However, the front light only operated for a short while after we bought the trailer and I don't know if the side light ever worked for us. Both have good light bulbs and I've switched known working bulbs to test the fixtures. No luck.

Next, I tried my multimeter with varied results. The side fixture shows no power at all, so I need to take that one off to see if the connections are bad. The front fixture shows 3.48 volts when I touch the two leads to the poles of the switch. When I reverse them, it reads -0.00. I understand the lack of reading on the side light - no power or no ground. What does the 3.48 indicate for the front light? Bad partial ground? If so, where does it ground to? The fixture has a metal backplate with a white ground wire screwed into it. However, the fixture screws to the fiberglass, so no metal to ground to there. The front light did work for about a month after we bought the trailer.

Any ideas? By the way, I do enjoy learning from everyone here. Every day is a new adventure!

Kevin

[gordon2]

Originally Posted by Kevin A

...where does it ground to? The fixture has a metal backplate with a white ground wire screwed into it. However, the fixture screws to the fiberglass, so no metal to ground to there. ...

Almost certainly, the white wire is negative (which is ground) and the metal back plate is the local ground. The light socket should have its ground / negative side attached to the back plate.

Originally Posted by Kevin A

...The front fixture shows 3.48 volts when I touch the two leads to the poles of the switch. When I reverse them, it reads -0.00....

Are you touching both meter leads (pos and neg) to the switch? You should be looking for voltage with the meter neg lead attached to the neg side and pos lead to the pos side. The switch is going to be the pos side. One end will be energized all the time and the other side only when the switch is ON. The back plate, white wire, and / or outside of the socket will be negative.

If its a digital multi-meter then they can show weird readings at times, such as when both leads are attached to the positive side of a voltage source. The reading will often vary rapidly over a wide range. Disregard these bogus readings.

[Kevin A]

Thanks. Heading outside to do some more testing this morning. I think both non-working lights may just have no power, so I'll have to track down those lines and fuses.

[Kevin A]

OK, several lights fixed today. Two of them had bad switches and one had no power at all. I replaced the two with bad switches and they now work fine. I also replaced one that was working but the switch was flakey, so I just took care of it before it fails. The one with no power will need more investigating. The wires run down through the front wall insulation and under the floor, so I can't easily trace them back to a live source. I may just have to run new hot and ground wires to the fixture and forget about the original wires. That's for another day!

[polskasila]

Yes, my side marker lights did not illuminate as I was preparing for a trip!
Take a look at the camper elec socket terminals and see if there was even a light coating of corrosion. I did have a light coating. I took a mixture of white vinegar and salt 2 tbls just enough to immerse the connector in a cup or glass for 2 min. Afterwards dunk conn in a glass of water with some baking soda to stop the vinegar activity.
Now my connector terminals are pristine. I blew out the contact area with air and tapped the connector to allow the moisture to run out downward. Finally sprayed the terminals with silicone. My lights came right on!!! I also make sure to tie a plastic baggie around the conn to avoid it getting exposed to the elements while idle.
Good luck my friend!

[mary and bob]

[QUOTE=polskasila;754630]Yes, my side marker lights did not illuminate as I was preparing for a trip!

I read Kevin's problem as being the exterior "porch" lights, not marker lights. Kevin ??

[Kevin A]

Right, it was the porch lights. However, advice about marker lights is always appreciated, too! They can be flakey little buggers, too.