Interior lights not working

Elizabeth · 07-07-2018, 09:57 AM

Help! We bought a 2008 T139 last year and absolutely love it. We took it out a few times successfully with everything working great. Last weekend, our interior lights started acting up. Sometimes they would turn on, other times not. Everything else is working - plug ins, microwave, fridge. Everything except for all the interior lights. We’ve checked all the fuses which appear to be just fine. Any suggestions?

profdant139 · 07-07-2018, 04:50 PM

Hmmm. Does your trailer have a control panel for the lights right near the bottom of the front door? And if so, are there "rocker switches" that control the lights? Once in a while, the wiring can partially pull out of those switches, making intermittent contact.

On our old 2003 T-139, we accessed the inside of that panel from inside the closet. Very tight quarters for a re-wiring job, but not impossible.

code2e · 07-08-2018, 01:30 PM

The things you mentioned as working, all run on 120 VAC rather than 12 VDC. All the lights are on 12 VDC as is the water pump, radio, range hood fan & shower fan. Do all those work except the lights? I would check the battery for at least 12 volts. Often there is a master 30 amp fuse at the battery box also. I have seen many fuses that look good to the eye. When tested with a test light or voltmeter, they are bad. I believe you have a power supply issue rather that any of the lights themselves.

Elizabeth · 07-08-2018, 02:28 PM

Thank you! Code2e, I think you’re right. We unhooked our battery recently because it was almost dead and the propane detector was beeping. This electrical issue happened shortly after that. The other features you mention (hood fan, bathroom fan, radio, along with all interior lights) are not working. We just checked the master fuse by the battery box and the cap was off and it looked really dirty. We’ve replaced that with a spare master fuse we had in the camper; no success with light and other, however I’m hoping once we replace the battery after we get home from camping tomorrow that solves the issue.

N&K · 07-08-2018, 03:15 PM

When you are "checking" the fuses, are you looking at fuse or do you have a tool to check like a volt meter? A small cheap voltmeter would be useful to tell you whether the fuse is bad by checking the continuity of the fuse or whether it might be the battery by checking the voltage of the battery. From the description you gave it could be either of these things, most likely the battery or the battery connection.

If you are going to replace the battery anyway, check the voltage of the old battery. This might give you an indication of whether the problem might reoccur.

Elizabeth · 07-08-2018, 03:25 PM

Thank you N&K. We do not have a voltmeter but we will definitely buy one. We’ll also check the voltage of the old battery.

anthonyx2 · 07-09-2018, 08:04 AM

When that main battery fuse is bad/poor connection/dirty, the battery also won't recharge as you drive. Keep that fuse/connection clean and make sure the cap stays in place. As an added bonus, if your battery is dead, your breakaway emergency brakes won't work, but that's a real worse case scenario thing.

profdant139 · 07-09-2018, 09:12 AM

Elizabeth, a cheap voltmeter is your best friend -- check the battery in the morning (before much use) to make sure it is at 12.1 volts or more. Drawing down below that will shorten the battery's useful life, as I have sorrowfully discovered.

Elizabeth · 07-10-2018, 06:35 PM

Thank you everyone! I’ll let you know how this turns out.

Hilda · 07-10-2018, 07:03 PM

good advice from all. Also, sometimes simple things get overlooked. are the wires to the battery hooked up right and making good connection? do you have pack rats or mice? they love to chew wires. Also, there may be a fuse along the positive battery wire. On another camper we had, that fuse didn't always seat properly, and the 12v wouldn't work until it was pushed in tightly.