Last week when we were in Renton, we tested Patterson’s headlights and discovered the foot-based dimmer switch wasn’t always working correctly. After a little research, I discovered the CJ-3A page had a useful thread on the topic, but naturally the switch demonstrated wasn’t exactly like the DJ-3A switch. The one shown on the CJ-3A page had a square end, while the DJ (and I’m assuming others of the same vintage?) have a rounded end. In fact, It isn’t clear to me which models use which dimmer switches?

Example dimmer switch from the CJ-3A page forum.
So, here’s a look at Patterson’s switch. The first obvious difference is that the housing doesn’t have tabs. Instead, it has crimps and, let me tell you, those crimps wouldn’t bend easily outward.
Using a small screwdriver, I eventually got the crimps straightened. As soon as I tugged at the top part to remove it, everything kind of tumbled onto the table (oops).
- #1 is the bottom piece. When the actuator is depressed it catches on #1 on the bottom of the piece and spins it.
- The metal tab that sticks up on #1 connects to #2 and spins it. #2 is actually made up of 3 pieces a) the disc, b) a shaft, and c) a spring.
- #3 is a copper propeller that rotates in conjunction with #2 and #1 each time the actuator is depressed. As you can see, it is very dirty.
- Part #3 connects with copper highpoints on #4, which shifts the electricity from the high beam to the low beam, then to the high beam, etc, in a circular pattern. The contacts on #4 were dirty, too, but hard to clean without scraping the copper points. I did not have a good cleaner handy, so I only gently cleaned them.
- This is a gasket.