So I thought I fixed this issue when I changed out the halo headlights for standard headlights from LMC Truck but the problem came back again. The headlights alternate between standard brightness and way too dim to see anything. The problem doesn’t start occurring until the truck has been driving for a while and it seems to happen more when conditions are foggy or rainy. Any ideas as to what is causing this?

 

Can't see the video because I don't have the "proper codec" and don't feel like paying a buck and taking the time to upload it to my computer. sorry 'bout that.
I did get the audio interestingly enough!

So are they for sure just going dim, or are they going out altogether?
If you are able to drive around in an area that is not too sketchy for not having as much light, you could disconnect one headlight and leave the other on to see what happens. Just trying to determine if the system is overloading for some reason (old tired headlight switch for example) and if halving the load stops it from occurring.

Just wondering if the wires or the switch are compromised and the built-in circuit-breaker is opening up. When it happens, how long does it last?
Is your wiring stock, or new? Headlight relay system, or original design?


Paul

 

I would just use a headlight relay harness and see if that fixes it. They are only about 20 bucks.

 

.+1 on wiring 8n a headlight relay. The stock setup is not very good.

 

I am with nene on this one.....the only true way to finally eliminate all the minor and eventually major problems reference to every pre 1998-ish Ford Truck headlight problem, is to convert - installing relays for the hi and lo beam circuits.

The standard factory wiring travels a long way to power the headlight switch which takes all the load, and you really want the relays to take the load instead, in which you will do any headlight switch a favor !!!!!

I also highly recommend installing superior grounding with larger wiring and interlinking all of it to engine, frame, body, starter, cowling, clip, volt reg, etc., and greasing all the connecting points so they do not ever corrode, so that you will have hardly - if any electrical problems because of it.


Thanks to a Canadian Trucker (that admired my 1970 camper hauler) mentioning to me this potential topic a year before I started having this problem giving me a heads up, and thanks to this site after I first experienced the minor problems with intermittent headlights cutting out despite installing a new headlight switch and new dimmer switch (with a 6 gauge ground) back in 2010 - I made my own wiring harnesses for all four of my Ford Trucks, (still left my standard factory wiring intact bypassing it) and installed relays as a standard procedure now - always supplying 14 volts of power to the headlights - never had any 30A fuse ever blow out, dim lighting, or intermittent blackout problems anymore - going on 11 years in any of my four Ford Trucks so far.

This link is where I got the knowledge to upgrade - still a many thanks to this site !!!!!!!
https://www.ford-trucks.com/articles...ghter-brights/


Another link for additional ideas of upgrading posted by everybody else here with knowledge on this site as well :
https://www.ford-trucks.com/forums/1...g-upgrade.html

 

Wow, a North Poliano on the forum. Enjoying the sun shiny -12 temp?

The first thing to do is to replace the pin connected switch with the newer 1970+ switch which has blade connectors. Search the forum for the part numbers for the switch and wiring adapter.

 

Then install a headlight relay harness to help reduce the load on the headlight switch. Like they said you can pickup a plug & play relay harness on E Bay for $20. Takes half hour to install, well worth the time and money. I installed one on my 1971 F250.

 

I think you are thinking about the pin/blade ignition switches.
The headlamp switch for 1965/72 F100/350 was part number C5TZ11654A. That was replaced by part number D3ZZ11654A switch and bracket kit. This is a Mustang part number so many Mustang repro parts companies carry it. Including Scott Drake.