Our issue is when the back lights on our RV go on, the left one is brighter than the right. But the bigger issue is that the brake lights don’t go on at all. Thank you in advance. — Kathy, Fleetwood Expedition 38K
It looks like your taillight assembly is for both the taillights and the brake lights, which means they would use a dual filament bulb like an 1157.
The first thing I would do is swap the bulbs from the left to right and see what happens. If the left stays brightest, then it is the socket or wiring. If the right is now brighter, then it is the bulb and typically both filaments are lighting up. The 1157 has two pins on the side, one low and the other high on the metal base. These slide down a grove and are twisted and are very difficult to get in backwards. However, I have seen a few cases where the grooves wore out or someone forced the bulb, so make sure they are in the correct grooves.
Most manufacturers have gone to a plug-in style bulb. However, since you did not provide a model year, I can’t track that down. You should be able to pull out the bulb and get a model number. If the socket is bad or loose, you might be able to add a little dielectric grease, which you can get at most auto parts stores in a small packet. Insert a little of that on the base and it helps make a better contact. This is an example of an 1156, which only have one filament, but this gives you an idea what it looks like.
Brake lights not working
To troubleshoot the brake lights not working, first inspect the bulb to see if the filaments are broken. I doubt both sides are bad; however, I’ve learned never to say never when it comes to RVs. If the bulbs look good, use a simple 12-volt light tester and have someone turn on the key and push the brake pedal. This should send 12 volts back to the wires and socket. Make sure you check inside the socket, as that will verify the wire and socket if you have 12 volts, which would mean the bulbs are bad or not getting contact.
If you do not have 12-volt power, then check the automotive fuse, which should be with the chassis fuses. I’m not exactly sure where Fleetwood or REV or whoever they are/were put them. However, most of the time I have found them in a front driver side outside compartment. If the fuse is blown, insert a new fuse and try the brakes. If it blows right away, you have a short in the system somewhere and will need to trace the wiring back to the light assembly. It’s not an easy task and I would start at the back cap, as wires are typically exposed back in that area.
There are many “Gremlins” when it comes to lights such as the wiring, fuses, socket assembly and what else is connected in the automotive loom or casing. I notice you have a large bike rack that could be pinching something, and I would also assume you have a wiring harness for towing a car. This would have wires for the brake lights as a plug in and could have caused a short that blew out the fuse.
Troubleshooting steps. Check:
- Power at the fuse block
- Good fuse
- Power or no power at the light assembly
You might also enjoy this from Dave
Why do my RV’s lights only work for a few minutes when unplugged or with generator off?
When my RV isn’t plugged into shoreline power, the lights only work when I’m running the engine or generator. If those are off, the house lights only last a few minutes. Why? Thank you. —Daphne, 2000 Thor Infinity
Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”
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