Dimmer Switch Won't Work

[Cougar25]

First, let me say I think I've reviewed all the posts on this forum regarding the installation of dimmer switches to deal with the excessively bright lights. As a result, I bought a dimmer switch from e-trailer, the recommended vendor.

I have a 2021 Cougar 25RDS. I also have that iN-Command panel that controls most - but not all - of the lights. For instance, it does not control the three ceiling lights in the slide-out; there is only one on/off switch for those. So that is my first target.

I connected the e-trailer switch in accordance with the directions. The red wire is hot, the black wire goes to ground, the white wire goes to the light. It turns the lights on and off - but will not dim. I thought I had a bad switch and they sent me a replacement, but still, no dimming.

The factory installation is depicted in the attachment. One red (hot), a solid green and a green with white stripe to the light, and 3 whites for the ground. That by itself confuses me a lot. Again, the iN-Command does not control these lights.

If there is someone out there with more electrical knowledge than I have, please offer suggestions. I'm stumped. TIA

[notanlines]

Odd as this may sound, when I swapped the on-off in the two bedroom headboard lights to two rheostats they went immediately to bright only. I swapped the wires around, ground to hot, hot to ground, and they worked just fine. Give it a try.
I only had two wires, not three so be careful. You shouldn't need three wires for a light switch.

[flybouy]

Are the lights dimmable? Not all LED bulbs are dimmable. Were the wires in the camper verified with a multimeter?

[LHaven]

The photo is difficult, but it looks to me like you wired the green and white + wire to the switch white, and the white neutral wire to the switch black. If so, reverse them.

[LHaven]

Originally Posted by notanlines

I only had two wires, not three so be careful. You shouldn't need three wires for a light switch.

You do for an LED dimmer. The switch itself needs power and ground to run, then a third lead to deliver dimming power to the LEDs.

The dimmer I bought for my recent project had four wires, which I thought was ridiculous. It would have made sense if the two whites were mutually isolated to suppress hum getting into the power line, but the darn thing hums up the line like a beehive.

[notanlines]

Sorry, but both rheostats, not dimmer switches, in our headboard lights had two wires, not three. I can remove one and take pictures if it would help. And yes, all our lights, 66 of them, are LED. This a picture of the replacement LED's I've been using when one goes to pot in the RV.

[Cougar25]

The graphic on the back of the switch says:

HOOK UP:
RED = +12v
BLK= GND
WHT = LGT