[White 89]

it has happened a couple times already. My headlights turn on and off on their own. I don't know what it could be.

Any thoughts. Could it be the headlight switch.

[saldoggs]

check to make sure you have a good connection were the head lights plug into the body harness look to see in there is any corrosion

[93HatchsBFF]

the flicker when there on? or just like randomly turn them on?

[Modified88Dreamer]

Does this happen when your fog lamps are on?

[dr.gonzo!]

Originally Posted by Modified88Dreamer Does this happen when your fog lamps are on?

+1


its a common problem for the foxes. Try driving with your fog lights off for a while and see if it happens again. If it still flickers with fog lights off could be your alt/short?

[Modified88Dreamer]

Originally Posted by dr.gonzo +1 its a common problem for the foxes. Try driving with your fog lights off for a while and see if it happens again. If it still flickers with fog lights off could be your alt/short?

A common problem that can be fixed


^ HEADLAMPS-FLASH WHEN FOG LAMPS ARE ON

^ WIRING-HEADLAMP CIRCUIT-INADEQUATE GAUGE WIRE AND TERMINALS
Article No. 89-17-11FORD: 1983-89 ESCORT 1983-87 EXP 1987-89 MUSTANG


LINCOLN-MERCURY: 1983-87 LYNX

ISSUE: The headlamps may flicker on and off when the fog lamps are used for an extended period. This may be caused by overheating of the headlamp circuit # 15.

ACTION: Install new wiring, terminals, headlamp and dimmer switches. Refer to the following procedure for service details. Refer to the following application charts for correct parts usage.

Remove the headlamp switch. Refer to the appropriate Car Shop Manual, Section 32-02 for service details.

Inspect the switch and connector terminals of circuit # 15 for any heat damage such as discolored terminals or distorted connectors.

Perform normal diagnostic procedure if no heat damage is found.

Proceed as follows if heat damage is found:

Remove the terminals and wire (Circuit # 15, red/yellow) from both the headlamp and dimmer switch connectors.

Cut the wire as near as possible to the wire harness tape wrap and throw it away.

CAUTION: IF THE CONNECTORS ARE DISTORTED AROUND THE TERMINAL AREA, THEY MUST ALSO BE REPLACED.

Crimp new terminals to the correct length of 12 gauge wire and install them in the connectors.

Overlay the new wire along the existing wire harness and tape wrap it.

Install new headlamp and dimmer/ multifunction switches. Refer to the appropriate Car Shop Manual, Section 32-42 for Mustang and Section 32-40 for Escort/Lynx/EXP for dimmer switch removal and installation details.

[dr.gonzo!]

I did have a page that fixed the problem and allowed you to drive with just the fog lights on

[Modified88Dreamer]

That was gonna be something I was curious about. Usually its just an additional wire tapped into another, but I don't know which or how it works with a relay. I have the wiring diagram

[dr.gonzo!]

found it

Mustang GT Fog Light Fix


had to dig deep for that one lol

[Modified88Dreamer]

Awesome site Gonzo! Added that to favorites. Rep!

[1989Gt.]

yeah connection one open spot could screw them all up bro

[1slo5.0]

Like others have mentioned, its the headlight switch. Common problem, easy fix. Hopefully your harness isn't melted to all beat hell.

[trueblue01]

Originally Posted by Darrell Like others have mentioned, its the headlight switch. Common problem, easy fix. Hopefully your harness isn't melted to all beat hell.

+1 If you go to a salvage yard and find more than one good switch and harness end, snag them. Most of the ones I've found over the years have been so so.

[92hatchback]

yea i just fixed this problem with a new headlight switch and the harness right behind it... but now for some reason my dash lights wont go on when i turn the headlights on..

[Modified88Dreamer]

Is your dimmer switch turned all the way to the right? I think thats the direction you want it to go to light up the dash

[92hatchback]

lol yea its all the way to the right... i think i have a short somewhere behind the dash

[White 89]

yes it flickers when I have my fog lights on for a while.

[1slo5.0]

Originally Posted by White 89 yes it flickers when I have my fog lights on for a while.

Like previously mentioned, its the headlight switch.

[White 89]

i just have to indepentally wire the fog lights and problem solved RIGHT?

[nolife]

Yes unless your headlight switch is already damaged beyond that point.
The headlight switch connections deveolp high resistance connections (or bad connections) over time and it starts to burn up because of the high current running through it. If you catch this early enough, the switch might still be able to handle just the headlights. Even after wiring the foglights seperately, I'd still cleaning the switch contacts with some rubbing alcohol and something a little rough like a small screwdriver that you can get in there should help it last a little longer.

I've seen the various diagrams for fixing this. The easiest way IMHO is to cut the power line in the engine compartment that runs to the fog lights as it passes in front of the battery behind the drivers headlight. Place the relay there and power the fog lights from a new fused wire through the relay straight from the battery or the + post on the starting solenoid. All work is outside and easy to get to and you don't have to touch anything in the dash. You are still using the existing fog light wiring to turn on and off the fog lights through the headlight switch and the fog light switch but the power for the fog lights is coming from your new fused wire.