Headlights, Instrument Panel Blink on Trip

[Redwingrobb]

Okay, here's the situation that I encountered. I picked up the car on Thursday and was driving back to a friends house before we left on Friday. He told me that my headlights were blinking. He thought it might be the foot dimmer/hi-beam switch, so we went down to the local auto place and picked one up. I installed it that night and and everything seemed to work. The next morning (4:00 AM), we left. As I was heading out, my instrument gauge started blinking like a Christmas tree (headlights were fine at the time). About 10 minutes later I got on the interstate and was driving when the headlights started powering off and on (not blinking, but like you were using a dimmer switch). At that point, the instrument cluster lights stayed on. I then figured since I was right behind my car with my friend, that I would just follow closely, turn off the headlights and go only with fogs. I did that for about 10 minutes and then the fogs totally went out. I switched back to the headlights and the headlights started blinking, but the fogs came back on. The fogs did not do the dimming like the headlights. Is there the potential that I have yet another dimmer switch bad, fuses, or just some screwed up wiring? Robb :icon_dead

 

[68gt390]

Robb;
Check your headlight switch in the dash. These switch's have a tendency to overheat and melt the connectors over time. I had the same problem and replaced the headlight switch and wala - problem solved. You can also do a search here on the site for a thread that talked about that very problem.

Don :grin:

 

[our special]

Okay, here's the situation that I encountered. I picked up the car on Thursday and was driving back to a friends house before we left on Friday. He told me that my headlights were blinking. He thought it might be the foot dimmer/hi-beam switch, so we went down to the local auto place and picked one up. I installed it that night and and everything seemed to work. The next morning (4:00 AM), we left. As I was heading out, my instrument gauge started blinking like a Christmas tree (headlights were fine at the time). About 10 minutes later I got on the interstate and was driving when the headlights started powering off and on (not blinking, but like you were using a dimmer switch). At that point, the instrument cluster lights stayed on. I then figured since I was right behind my car with my friend, that I would just follow closely, turn off the headlights and go only with fogs. I did that for about 10 minutes and then the fogs totally went out. I switched back to the headlights and the headlights started blinking, but the fogs came back on. The fogs did not do the dimming like the headlights. Is there the potential that I have yet another dimmer switch bad, fuses, or just some screwed up wiring? Robb :icon_dead

Robb, it is a very good chance that the problem is in your headlight switch.
I had a very similar problem with mine with the headlights flashing and I would have to pull in to the side of the road, turn off the switch until the relay cooled down. I would then drive on again until they started flashing, pull in again, and so on and so on.
Remember, we used to trade in our cars when they started giving trouble like this, but now we are spending big bucks to buy them. Go figure!!! LOL
Dave

 

[Powell]

headlights

I agree with Don, I had that same problem several years ago and spent a long time trying to figure out the faulty part. In the end it was the head light switch on the dash. The tale tale sign was how Hot it got after the lights had been on for a short period of time. A trip to the local NAPA parts store for a new switch solved my problem.

Ralph

 

[390cs68rcode]

I have replaced 3 headlight switches in 3 different cars recently. It is your headlight switch.

 

[Redwingrobb]

Thanks for the input. Somebody today told me it might be the relay. Any possibility of that? Robb

 

[390cs68rcode]

Thanks for the input. Somebody today told me it might be the relay. Any possibility of that? Robb

doubtful

 

[Mosesatm]

Robb, the problem with the headlight switches in GT/CS is that they were designed for 2 headlights and 2 taillights but they are now running 2 headlights and 6 taillights. As long as all the grounds and contacts are perfect everything works ok but if any of the taillight sockets get a little corroded or a ground loosens a little the added load on the headlight switch fries it. When you buy your new switch it might be a good idea to buy another as a spare. The odds are you will need it some time in the future.

How about this one? All my lights work great except for the rear turn signals. The emergency flashers work, the brake lights work, the taillights work, and the front turn signals work.

Any ideas?

 

[case12]

Another suggestion to cool down the switch (after the burnt up one is replaced) is to switch to LED taillights. I did this with the sequential type LED taillights and love them. They twist right into the taillight sockets ----No changes required to any wiring. You can search for several threads on this on the site about the LED and sequential taillights. Casey

 

[390cs68rcode]

I second the LED taillight thing. I have them on all my cars.

 

[rvrtrash]

One more thing to think about. Have your headlights been replaced with halogen bulbs? If so you are drawing to much current through your headlight switch and the breaker in it will cycle on and off just like you described. It happened to me on another Mustang.
Steve

 

[Perkchiro]

Robb, the problem with the headlight switches in GT/CS is that they were designed for 2 headlights and 2 taillights but they are now running 2 headlights and 6 taillights. As long as all the grounds and contacts are perfect everything works ok but if any of the taillight sockets get a little corroded or a ground loosens a little the added load on the headlight switch fries it. When you buy your new switch it might be a good idea to buy another as a spare. The odds are you will need it some time in the future.

How about this one? All my lights work great except for the rear turn signals. The emergency flashers work, the brake lights work, the taillights work, and the front turn signals work.

Any ideas?

Turn Signal Flasher?

 

[Mosesatm]

Turn Signal Flasher?

I hope so since the only other option I can think of would be the turn signal switch, and I really don't want to go there.

Does anyone know if there are front and rear wires coming out of the flasher or is it just one main wire that runs all the lights?

As soon as I get this turn signal thing fixed I can get it inspected, insured, and licensed!!! :icon_ecst

 

[rvrtrash]

Sorry for the bad news Arlie, but the turn signal flasher is before the turn signal switch with one wire in and one out. If the front are working, it's not the flasher. You might want to try buying some electrical contact cleaner and spray it in both sides of the connection from the T.S. switch at the bottom of the steering column. Sometimes the connections build up some oxidation and the current doesn't get through. It's a lot cheaper and easier than replacing the switch.
Steve

 

[Mosesatm]

Good idea, Steve.

I studied the wiring diagram last night and came to a similar conclusion but I figured that when I gutted the interior I might have pulled or cut the two wires that lead to the rear of the car. Never even thought about the connectors. It could also be that the wires pulled out of the connector. Looks like I'll be upsidedown tomorrow night tracing wires and connectors.

Notice I said, "tomorrow night" and not "tonight". I may be dumb but I'm not insane.....yet.

 

[rvrtrash]

Notice I said, "tomorrow night" and not "tonight". I may be dumb but I'm not insane.....yet.

Give it time, you'll get there.:frust: :rofl:
If you're going to be under there for a while, think about pulling the seat out. It's a tight fit with it in the way.
Steve

 

[Mosesatm]

Ah ha, found it, found it, found it!!!

There is a connector in the dash that connects those 2 specific wires. Orange with a blue stripe and green with a orange stripe. Pushed the connector together....instant turn signals!

What's interesting is that I started in the trunk and noticed that the wiring harness has been stripped off every 12" or so. Apparently someone else was looking for the same problem. Maybe that's why the last tag is dated 2001. The only way to find the connector is to remove the HVAC controls or the gauge pod and that was probably a daunting prospect for the previous owner. Luckily my HVAC controls are out of the car so it was an easy catch.

Mustang restoration is kind of like golf, it takes only one good shot or one easy fix to make it all seem worthwhile.

 

[390cs68rcode]

or one easy problem you cannot figure out to ruin your day. ask me how I know.