Flickering headlights

[Red's FSJ]

Hello, hoping someone can lead me in the right direction with my 76 Wagoneer, 401.

The headlights/all lights were flickering so I went ahead and swapped out the headlight switch. The problem persists. It seems to be more intermittent now though but still does it most of the time. What else can I look into to fix this issue?

Thanks!

[Amc71601]

Sounds like an issue with the ground for the lights. There's a member here in the homegrown vendors section that makes replacement wiring harness for these too.

[serehill]

yep

Is it just the head light that flicker or all lights that flicker? Although the harness is a great asset I would recommend the dimmer switch be replaced if it is indeed just the headlights. Then install the harness.

[joe]

Lessee you're in CT with that wonderful fun stuff "road salt". The older floor mounted dimmer switches repeatedly getting wet are highly prone to corrosion to going completely south in time. Add the joy of years of salt and the floor dimmer would be my first suspect. Often the ground between the switch and sheet metal floor is all it is but 1976 huh, the entire switch itself is likely toast. The OEM switches were pretty good quality and unfortunately new Taiwan replacements aren't. Since you've got a new headlight switch already, if it's not the dimmer I would chase down and clean the grounds at the lamp end.

[Red's FSJ]

All lights are flickering. The truck is very clean with very little rust. I will take a look at the dimmer. The interior dome lights do not flicker when the headlights are off, but when they are one, every light flickers, dash, dome, parking light, etc.

Thanks for the responses!

[joe]

I'd still bet on the dimmer. If bad it'll affect the dash lights too. Once it gets real bad it'll shut all your lights off. From there while driving down the road you're left with jumping up and down on the switch hoping the headlamps at least come back on. Drove off the road and rolled a VW playing that game.
If it just getting flakey occasionally, while driving down the road and all the lights are behaving tap on the switch with the side of your boot and see if things flicker. It's a cheap enough part to risk your money on.

[serehill]

OK better input

All the grounds for reach light are independent of each other so if it is a ground which it could be. The issue would be a larger ground like the ground strap that goes from the motor to the body ETC. It won't be the ground going to the light switch it only operates the dome light. It also can be a loose connection on the positive under the dash or fuse block as a last resort.

[Red's FSJ]

Thanks to all. I will replace the dimmer and check on the fuse box as well.

[Tornado230]

Check the grounding of the voltage regulator.
It's grounded through the base, but the ravages of time affect it.
Run a wire from the - post of the battery to the base of the regulator.
See if that makes a difference. It did for me.

[Carnuck]

Right before my ammeter had a total meltdown while driving my lights did the flicker thing.

[AMC-COMMANDO]

Did you ever solve the problem? I am experiencing the same exciting issue right now. New head light switch and dimmer switch, new ground from battery to the fender. Yet the problem still exists!

[johnsonic]

Since this thread is back from the dead, I had an '87 totally gone through in a bad way by the PO - found that one of the headlight wires was rubbing against the headlight bucket and had worn through the insulation. Just putting it out there as something that happened to me and caused the same issue.