Headlights randomly shut off

[Rot Box]

I keep having this problem where both headlights will randomly shut off. It is not all the time, but enough that I don't trust it. It does it on high and low beams but if I hit the dimmer switch I can usually (sometimes not for awhile) get them to come back on with a few clicks/toggle... I have been through two dimmer switches now and I'm starting to think it is something else

Any known issues or things to check? I drive home from work every night and it really sucks when everything goes black out in the boonies Thanks!

Andrew

 

[DragRag]

It is usually the headlight switch or the plugs that plugs into it. I have had a bad plug/harness in my 91' F250 before and had to change it out. Pull your headlight switch and check the plug, I bet you will find it there.

 

[lotzagoodstuff]

+1 on the switch, do the relay mod and it should last forever.

 

[Abull78]

x2 switch

 

[rjjp]

X3, Its a common problem, here read this:
http://www.ford-trucks.com/article/idx/8/039/article/Whiter_Whites_Brighter_Brights.html

 

[MIDNIGHT RIDER]

Ford head-light switches contain an internal bi-metal circuit breaker.


When this breaker fatigues from age and too much heat, it will start tripping, thus shutting off the lights.

When the breaker cools, the lights will come back ON.

Back in the 80s, a bunch of trucks got sold that had faulty breakers and would exhibit this problem even when new.


A new head-light switch will have a new breaker.


Best is to do the relay/big-wire modification and remove all the load from the over-taxed factory set-up.

 

[subway]

got to agree with everyone here, it has happened to me to i know how much it sucks. i couldent trust driving my vehicle at night.

 

[Rot Box]

Oh dang you guys are awesome!

The mod looks pretty strait forward I think I found my weekend project. Anyway thanks everyone for all the help

EDIT: Oh and the best part was don't attempt without beer... I can definitely handle that one! lol

 

[Agnem]

Probably the weirdest thing I ever had happen to me.... I remember it distinctly. The wife and I were driving along in the Moose Truck many years ago, and I was reminiscing about my family's 65' Ford Custom that we had, and I was telling her how the headlights would randomly go off and on, and how my mom had some shop rig up a different switch (I guess because a replacement wasn't available ) to work the headlights. I had just finished telling this story and we were riding along in silence, when all of the sudden the headlights in the Moose Truck went out.

Talk about freaky.....

 

[tuckerd1]

Probably the weirdest thing I ever had happen to me.... I remember it distinctly. The wife and I were driving along in the Moose Truck many years ago, and I was reminiscing about my family's 65' Ford Custom that we had, and I was telling her how the headlights would randomly go off and on, and how my mom had some shop rig up a different switch (I guess because a replacement wasn't available ) to work the headlights. I had just finished telling this story and we were riding along in silence, when all of the sudden the headlights in the Moose Truck went out.

Talk about freaky.....

..and your wife thought you were playing around.

 

[Rot Box]

^

If I get a new switch will it handle the lower voltage better than the one I have? The relays are the best idea, but I need something to just get me by for now

 

[rwilles]

Hey Rot Box I've had this happen in two different trucks.

1) Green f350, standard headlights, started flickering on the last road trip. Took an hour to swap the dash headlight switch out in the 24 hour Auto-zone parking lot in a very interesting part of Orlando. It was 1AM and not the time or place for a white boy with two kids!

2) Red f150 with Xenon bulbs (higher load possibly?) burned the block that the switch plugs into. Had to get new block and downgrade the bulbs. The relay thread looks interesting!

 

[82F100SWB]

I did the relay mod on my 460 truck many years ago, with a failing circuit breaker in the switch, and, I still have yet to replace that switch...
However, with the 100/50W bulbs I'm running and the fact I have the highs wired so it's both high and low(lows are bypassed at the dimmer so they have power as long as the headlight switch is on, it only switches the highs on and off) I've been melting the headlight plugs. Still need to come up with a better plug for them.