Headlight wiring and dimmer

[rreegg]

Hey all,

I'm finally looking into some headlight issues that's been on/off (no pun intent). Believe to have fixed the root of the problem which was water penetration through the clutch master cylinder hole in the firewall. Some water entry has corroded the headlight dimmer switch on the floor. I'm looking to replace this foot switch with a hand rocker.

I’ve also seen some people mentioning upgrading their headlight wiring to use relays as well..

My question is: I only get the low beams and no hi beams. With a voltmeter I get 12v on both the hi and lo circuits from the dimmer switch. Which leads me to think the high beam circuit is likely open on the way to the lights? (From the dimmer - light switch to dimmer seems continuous)
Should I bother with tracing down these wires or just replace the headlight wiring with a new harness?

Any thought or more troubleshooting tips is appreciated thanks

 

[rreegg]

eBay has some pretty cheap relay harness from a vendor called j87 or something, they ship from Roseville ca and seem worth a shot

 

[Big Bart]

I bought the kit below to install, just been too busy with my sons car to do it.

It still requires the wiring inside the cab to work. So you may have to chase down the issue. I believe the switch on the floor has 3 terminals. 1) Power to the switch. 2) Power out to low beams. 3) Power out to high beams. But I do not recall if it powers the low beams and high beams together on the high beam setting. Check your grounds since the problem comes and goes. If not fixed then put the lights on high and start wiggling wires to find if you have a short.

Here is what I bought.

1987-1991 Ford Bronco & F-Series Truck Heavy Duty Headlight-Broncograveyard.com

Upgrade your headlight's wiring harness for maximum light output with a Heavy-Duty head- light harness. If you are adding brighter bulbs or upgrading to high power halogen lights. then you need to improve your wiring to take full advantage of the extra light output.br This Heavy-Duty Harness is...

shop.broncograveyard.com

 

[Danielle]

I made my first one using the tech articles from this site, but then bought the bronco graveyard for my second one.

I got these eBay Chinese lights and they work a lot better than what I had. They're just upside-down haha (that's how they are designed)

 

[Big Bart]

I should have also mention you should probably pull your headlight switch in the dash and check the wiring harness and the switch. These go bad from handling too many amps as they do not use a relay. Thus why the headlight relay package above is recommended. It takes the amperage strain off the headlight switch and cab wiring harness.