I love our little Sunray 109 Camper. It’s a very efficient feature-packed trailer, right down to the use of LED lighting. That LED lighting is positioned perfectly in various spots and it’s very bright which is normally a great thing – except when you want to relax at night.
There’s a couple of dimmer solutions available that you can wire in yourself. Some of them have mixed reviews. When I studied them, I realized that the poor results some people were seeing with these dimmers was a combination of two things: They selected the wrong type of dimmer, and they were not installing them properly. So I set out to find the solution that works.
Campers, like boats, don’t actually have a “chassis ground” like you’d find in automotive wiring. This is because you have two different electrical systems: An 120-volt AC electrical system, and a 12-volt DC electrical system. So manufacturer’s cannot mix AC “ground” with DC “Chassis ground”. As a result everything has its own wires and the 12-volt DC accessories always have two wires: Positive and Negative.
LEDs (Light Emitting Diodes) are a highly efficient alternative to incandescent light bulbs but because they are semiconductors at their heart they have some limitations in how they function.
The key to success and to overcoming these challenges is that you have to select a 4-wire PWM dimmer. As mentioned above, boats and RVs have their own low-side wires which makes wiring this much easier.
I recommend, and have had great success with the “Obeaming” 4-wire dimmer available on AMAZON. I’ve had great success installing it in my Sunray 109 Sport Camper. The photos below walk you through the wiring for the interior lights on that model camper.
