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Does anyone have any guides on how to make a dimmer for halogen lights? ? Answered

I'm trying to install a dimmer in my car for 2 fog lights. they're about 40 watts each. I would like to be able to dim these bulbs. Thanks.


Most halogen lights are 12V. so look at these.  There are some circuits and some prebuilt dimmers.  There should be something useful here.  You could even use pwm dimming.

What determines if a prebuilt dimmer would work or not? I was told not all 12v dimmers would work. If possibile i would love to just locate a cheap dimmer and purchase that. Has to be small though.. under 2.5" in height. and width.

Just look for a 12v. dimmer labeled for halogen lights.  It must be 12v. though.

does watts play any part in selecting a dimmer? do you recommend a site or any particular product?

Yes watts on the dimmer must exceed total watts in you lights.

I would just find what I wanted on the net of locally and buy.  I have no preference over site or product.

You don't dim fog-lights, they're supposed to be bright. Why do you want to do this?
Maybe switch them between series & parallel if you have to?


I'm trying to customize fog light bulbs into my reverse lights. I want to be able to dim them as not to blind people when full power is not required.

Right. Reversing lights should not be red, you would be better modifying the one(s) you have I think. If it's for reversing, mess with what you have for reversing


dont think i ever mention that i wanted them red..... i figured out a way to use 893 bulbs in place of the stock 921.

Oh right, I get it now. Go with what Re-design is talking about.