Headlights won't stay on

DaBird93

Registered User
My headlights flicker and stay off while driving .. If I go and turn on the high beams it's ok but sometimes they will flicker and go on and off.. Which switch is going bad? Is it the dimmer? Really getting bad need some help..
Thanks...
 
Could be the little metal relays in the fuse box. I had that problem when I had so "better" bulbs in my car. The relays burnt up and even after changing the bulbs I had to replace them as well. Little metal things slightly larger than a fuse in the fuse box.
Alan
 
Could be relays.

From experience and reading other's experience, I'd bet the MFS (the "dimmer" as you call it) dying.

Word of caution: I'd convert to a relay harness for the lights along with swapping the MFS.

Also, I'd opt for a new MFS.

I'd also check the head light switch itself - there's several I've seen in the boneyard that almost burned up at the switch (!!!)

RwP
 
My headlights flicker and stay off while driving .. If I go and turn on the high beams it's ok but sometimes they will flicker and go on and off.. Which switch is going bad? Is it the dimmer? Really getting bad need some help..
Thanks...

Multifunction switch is my bet. Take the plastics off the steering column. Check the wiring harness going to the multifunction switch. If it is burnt, I'll bet 10 to 1 that you have a bad multifuntion switch for sure. If thats the case replace the pigtail harness also or you will be doing the job again soon.

Chris

If you are playing with the multifunction switch to get lights to come back on, thats probably your issue
 
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Headlight switch, happens to every Ford (and most Dodges too) at least once in it's lifetime.

10 minute swap in the parking lot with a phillips screwdriver, pair of pliers (for the mounting nut) and a pick (to remove the switch knob).
 
Ill start with the headlight switch and go from there hopefully that solves it I'll keep everyone updated..
 
isnt the headlight switch i am having the same problem with mine i replaced relays headlight switch idk im going to go with the dimer next and see how that works out
 
I believe the multifunction switch is seperate from the dimmer/on/off switch that is why the highs work still
 
same thing happened here. i didnt have to replace the switch though. for a temp fix that became long term i ran a sub-relay system to power the headlights using the signal from the switch only to control the relays. havent had another issue so i left the headlight switch in there.
 
Here is a pic of what you might expect to see when you take out your headlight switch.

I also include a pic of my relay fix to stop line voltage from going through the headlight switch and the MFS.

As I said in a related post I picked up 2 volts at the light bulbs by eliminating 20 some odd feet of small gauge power wiring.

Regards

Sean
 

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Here is a pic of what you might expect to see when you take out your headlight switch.

I also include a pic of my relay fix to stop line voltage from going through the headlight switch and the MFS.

As I said in a related post I picked up 2 volts at the light bulbs by eliminating 20 some odd feet of small gauge power wiring.

Regards

Sean

nice relay layout. i just stuffed mine down infront of the batt
 
nice relay layout. i just stuffed mine down infront of the batt


Thanks.

With all the changes to my car I am now going to affix them to a longer piece of UHMW so I can change the mounting location.

THat piece was mounted where the air cleaner was. Now that I'm changing back to a stock air cleaner box I'm going to mount them at the front of the engine bay.

regards

Sean
 
Here is a pic of what you might expect to see when you take out your headlight switch.

I also include a pic of my relay fix to stop line voltage from going through the headlight switch and the MFS.

As I said in a related post I picked up 2 volts at the light bulbs by eliminating 20 some odd feet of small gauge power wiring.

Regards

Sean

YUP, thats what happens to the headlight switch!
BURNS UP or melts!

Great looking relay set up!
Post the link to the thread you did this in?
Would like to see better and more detailed pics/info on this.
Looks like you are running a relay per light?
 
Why do you have individual relays for each light and not just one for Hi and one for Low?
With 12g wire voltage drop wouldn't be an issue, especially if mount closer to the battery. Most likely 14g is fine but I usually go up a size on DC.

Voltage drop with 14g is 1.6% and with 12g is 1%. Both are acceptable but I'd still go with the 12g. 10g would be ideal but I doubt worth the cost.

To the OP the issue is the dash headlight switch. It is over heating, between it age and all the lights (parking, head and instrument) its borderline.
 
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Why do you have individual relays for each light and not just one for Hi and one for Low?
With 12g wire voltage drop wouldn't be an issue, especially if mount closer to the battery. Most likely 14g is fine but I usually go up a size on DC.

Voltage drop with 14g is 1.6% and with 12g is 1%. Both are acceptable but I'd still go with the 12g.


Well there IS the redundancy factor - as is, if one relay or one fuse blows, he's got the light on the other side still.

Me? I'm cheap, I used one relay for high and one for low. Will be adding one for fog if I ever find the brackets for factory fog lights on the 1991 Cougar (hint, hint!)

RwP
 
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