Headlight LED Dimmer

[yurtle]

I have a DPDT headlight switch from when I had halogens, to do parallel and series. I now have LED headlights with a dimmer, and I'm gonna wire them up so up is head and tail lights bright, middle is off, and down is dimmed headlights and full tail lights. I sketched something up and it will work, but I hate providing power to my dimmer when it's not dimming. Dimmer has a common +in and +out.
I'm having a mental block.
Suggestions?

[kernal]

Originally Posted by yurtle

I have a DPDT headlight switch from when I had halogens, to do parallel and series. I now have LED headlights with a dimmer, and I'm gonna wire them up so up is head and tail lights bright, middle is off, and down is dimmed headlights and full tail lights. I sketched something up and it will work, but I hate providing power to my dimmer when it's not dimming. Dimmer has a common +in and +out.
I'm having a mental block.
Suggestions?

After looking at that diagram, are you sure your not having a stroke!

[Volt_Ampere]

I am an EE and I can't read that diagram.

[yurtle]

All I can say is LED dimmer has a common 12 volt + in and + out, so all three LEDs have 12 volt + all the time (when key switch is on the third position). When DPDT switch is up for high beams, the 12 volt - goes to tail light and both headlights. When DPDT is down, tail lights still get full 12 volts, but headlights are fed from the dimmer. Remember, for a DPDT switch (or any toggle for that matter), when the toggle is up, the lower terminals are in use. Kinda makes sense if you've ever torn one apart.

[yurtle]

Oops, just noticed my diagram had I and O backwards on the dimmer. Works, but can't think of how to kill power to the dimmer when on high beams, using existing DPDT switch.

[coosa]

Couldn't you mount a toggle switch somewhere on the wire to the dimmer and keep it off except when you think you might be using the lights?

BTW, I like the diagram. :)

[Sergio]

It is always a good idea to switch off the positive to all loads.

Try this using what you have:

[yurtle]

I already have a DPDT switch on my dash. I had a separate switch for tail lights, but figured if my headlights are on, my tail lights would be too. I moved the dimmer pot to the old tail light switch location. I figure the dimmer pot will be a set it and forget it kinda thing. I was originally gonna keep the pot on the dimmer box, which will be mounted behind the dash, but changed my mind.

I keep my ugly sketches in a folder called "shoulda been". After installation, I do a Visio "asbuilt" drawing.

You'll notice all of my wires have industrial number labels.

wow that is one dirty cup holder

[yurtle]

Originally Posted by Sergio

It is always a good idea to switch off the positive to all loads.

Try this using what you have:

Much purtier than my drawing, but it still has power to the dimmer in high beam and low beam. Switching + or - makes no difference in a buggy, where the frame is neutral. For a car, I agree.

FWIW,
All my switches are DP, so up until now, I switched + and -.