12v Headlight conversion

[mobileauto2000]

I am tired of always replacing headlights. They are expensive and not available locally for me.
This morning both low beams were out and I only had one spare.

My truck has a 12 volt system. I use a battery equalizer to charge a third battery for 12v accessories.
So I decided to convert to 12 volt headlights. Here is how to do it.

To start you must have a 12 volt system, you cannot just tap off of one battery as they will become unequally charged and shorten their life.

But if you do have 12 volts its an easy mod.

First you get a 24 volt continuous duty solenoid or relay, two 12 volt 7" headlights. You will need some 12g wire and a inline fuse holder. Also some crimp connectors and eyelets. I used a solenoid as it is what I could get my hands on today. A relay may be cheaper.

Mount your 24 volt solenoid on the firewall above the dimmer switch and using a wire ground one of the small terminals to a mounting bolt.

Next find wire number 16 going into the dinner switch, unplug it and cut it about one inch from the end.

Using a crimp connector splice a wire onto the the 16 wire coming out of the wiring harness. You will run this wire to the other small thermal on the solenoid. now when you turn on the headlight switch it will activate the solenoid.

Take the plug you cut off the 16 wire and splice a wire onto it. Plug it back into the dimmer switch and attach the other end to one of the large terminals on the solenoid.

Now we need to run a wire to our twelve volt source. This was easy for me as I have a disconnect solenoid for the 12 volt system mounted under the map box. (Almost said glove box and I heard Doghead correcting me in my brain). Connect this wire with your 12 volt source end and install a fuse.
(This picture is the solenoid mounter under map box) Notice the inline fuse.
Run the wire from your 12 volt source to the last big terminal on the solenoid and the wiring is almost done.

Now To install your 12 volt headlights. This is the place I did not make good notes.

You will need two headlight plugs. You can get these from any auto parts store.
If you look at the back of you 12 volt headlight you will see two terminals across from each other and one under them. If you now look at the 24 volt bulb you will see the wires are arranged the same way.

Make sure you orientate the bulbs with the top up when comparing. Cut the wires off the 24v headlight and splice them to the same location on the 12v headlight plug. Now install the 12 volt headlights and enjoy.




(Prov 12:1 [NKJV])
Whoever loves instruction loves knowledge, But he who hates correction is stupid.

 

[wreckerman893]

Or you can bite the bullet and get some of the new LED headlights. I picked up a set at the GA Rally for the M927 and they are the cat's azz for night time driving. Pricey but worth it.

 

[m-35tom]

strange, i have had deuces for almost 20 years and never had a bulb burn out. critical is to have the idle speed set correctly and have good mounts on the light assymbles. a 12 volt bulb will burn out just as fast as a 24 volt one if you give it the same environment.

 

[Speedwoble]

I bought 7" Lightbulb housings from Amazon for $38 and use 24V H4 bulbs @ $8 apiece.

 

[mobileauto2000]

strange, i have had deuces for almost 20 years and never had a bulb burn out. critical is to have the idle speed set correctly and have good mounts on the light assembles. a 12 volt bulb will burn out just as fast as a 24 volt one if you give it the same environment.

It has more to do with the quality of the bulbs. I but in three of the made in china lights you get of ebay and they all failed almost instantly. One lasted a whole two days.

I switched the one original GE light from the other side to see if it was a problem related to the one socket and that bulb did not fail for two years until now.

I found some old American made 24 volt non military lights on ebay cheap and had no problems with the other one for over a year.

I drive the truck six days a week with the lights always on so I am not surprised that they need replacing again considering the vibration they live with.

I want the factory look so composite and led lights are out.

Also because it it my main transportation I want bulbs that I can get any where.

Plus they are cheep and halogen so they are brighter.

You are correct about the Idle speed, I have mine set at about 800, any lower than that I get a nice massage.

Also as to the H4 conversion. I spent about the same amount of money for the parts and bulbs as the H4 conversion would cost.

A 7" halogen bulb has about the same candle power as the H4 and looks factory. (Not counting illegal bulbs)

Of course it would not have been cost effective if I did not already have 12 volt power on the truck.