Headlight issue
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Senior User
Joined: Mar 2021
Posts: 287
Likes: 54
From: WV
Headlight issue
I’m driving my 66’ 2hrs every Monday morning to work out of town. I leave at 430am. While running my high beams, I have totally lost my headlights a time or two. Is this a sign that my high beam switch is going bad?
See A Man About A Horse
Joined: Apr 2003
Posts: 4,897
Likes: 651
From: Mariposa, Ca.
Replace the dimmer switch, they are inexpensive. If it still happens, change the headlight switch, also inexpensive. Do you have higher powered replacement headlights? They could be the problem. In that case, consider using a relay system to lower the current through the headlight switch
Fleet Owner
Joined: Jun 1999
Posts: 24,552
Likes: 74
From: Creedmoor, North Carolina
Dadgumit, That used to be an issue across the Ford truck board. We made some changes the wiring source and stopped it. I can not remember zackly what we did. We worked on the wiring changed the source of power as well as grounds. We ended up with brighter lights.
I wish my rememberier worked as well as my forgetter.
John
I wish my rememberier worked as well as my forgetter.
John
See A Man About A Horse
Joined: Apr 2003
Posts: 4,897
Likes: 651
From: Mariposa, Ca.
Even replacing the dimmer and headlight switches and improving the grounds - if you’re using much higher wattage headlights or lighting systems than stock, it can overload the circuit breaker in the headlight switch assembly, and cause it to trip. It would be more likely to do this at night using high beams.
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Fleet Mechanic
Joined: Jun 2019
Posts: 1,898
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From: Southern California
On the homepage of this FTE website, there is an article titled "Whiter whites, brighter brights". It explains the problem, Too much resistance in the headlight circuit causing the thermal breaker in the headlight switch to trip, and gives complete instructions to add relays to the system and eliminate the problem.
I was encountering the same issue and did the relay conversion last week. Fairly straightforward, It took me about three hours but I cleaned up a bunch of other wiring and added a fuse box at the same time. My lights are brighter and don't blink after being on for 30 minutes.
I was encountering the same issue and did the relay conversion last week. Fairly straightforward, It took me about three hours but I cleaned up a bunch of other wiring and added a fuse box at the same time. My lights are brighter and don't blink after being on for 30 minutes.
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Senior User
Joined: Mar 2021
Posts: 287
Likes: 54
From: WV
Thanks for the info fellas!! To answer some of the questions, I have checked all of my grounds, I’m running sealed beam OEM headlights, low beams work flawlessly only issue is when I start running highs. One other question for you guys: Should I be able to dim my dash lights with my headlight switch or did they not do that in 66’?
I will look into replacing headlight switch and high beam switch 👍🏻
I will look into replacing headlight switch and high beam switch 👍🏻
Thread Starter
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Senior User
Joined: Mar 2021
Posts: 287
Likes: 54
From: WV
It must be toast then 😎
Fleet Mechanic
Joined: Jun 2019
Posts: 1,898
Likes: 234
From: Southern California
https://www.ford-trucks.com/article/...r_Brights.html
Here is the article. Just do it, it is THE fix. I( understand Toms Bronco Graveyard sells a harness with relays for this exact issue, if you are not comfortable with the wiring.
Dan TK65
Here is the article. Just do it, it is THE fix. I( understand Toms Bronco Graveyard sells a harness with relays for this exact issue, if you are not comfortable with the wiring.
Dan TK65
See A Man About A Horse
Joined: Apr 2003
Posts: 4,897
Likes: 651
From: Mariposa, Ca.
https://www.ford-trucks.com/article/...r_Brights.html
Here is the article. Just do it, it is THE fix. I( understand Toms Bronco Graveyard sells a harness with relays for this exact issue, if you are not comfortable with the wiring.
Dan TK65
Here is the article. Just do it, it is THE fix. I( understand Toms Bronco Graveyard sells a harness with relays for this exact issue, if you are not comfortable with the wiring.
Dan TK65
I used the harness from Tom’s Broncos. It has the needed relays, and uses a separate fused circuit for each of the high and low beams. There is even a diode which, when left installed, allows you to run both beams simultaneously, or remove the diode for normal operation.You will never have a problem tripping that breaker in the headlight switch again, as current will no longer flow through it.
Put in a new headlight switch.