Last week we installed a onewire alternator from an Aerostar onto the Comet. Everything went great with one exception. When I put the highbeams on, after about 90 seconds they shut off, then on, then off, on, off, etc. It only happend when the highbeams are on, low beams function fine.
Should I have installed a relay in the headlight circuit and would that correct the problem?
Headlight switches in that era of cars had a circuit breaker built right into the switch, looks like it is tripping.......Unhook one bulb at a time and see if it stops, feel the wires going to the lights too to see if they are getting hot...You might have a short or partial short. Cant see the new alternator doing this, but I am no electrician....
Two weeks ago the same thing going on with a buddys 72 Camaro his taillights and turn signals blinking. We looked and yup a taillight bulb ,sometimes the simple things just add up. Good luck.
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gotta be young and dumb before you get old and wise
Well now y'all got me thinking. When I bought this car the center highbeams didn't work - both burned out. I got tired of not being able to see at night and replaced them. Could be the previous owner had a problem he didn't mention. Also, one of the boxes was open, only two left on the shelf at CTC when I got them. Ah well, it's raining today so I'll spend some time in the barn. Poncho, I did feel the wiring and nothing was warm, moved them around some to see if anything was loose, no dice so I'll do as you said and dis=connect them one at a time. Might have to add a headlight switch to my wishlist at Mac's. I'm glad the Falcon only has 2 headlights.
Just my opinion, but with the car running put a volt meter across the battery terminals. It should be around 13-13.5 volts. The only thing that would cause bulbs to burn out is over voltage or vibration. I'm just wondering if the voltage regulator is the cause of the issues??
i had the exact same problem with my tow truck, drive for about 60 minutes and the headlights would blink off constantley. turns out i have so many lights going from my headlight switch that its exceeding the switches capacity. i changed the switch twice but they dont seem to last. i simply wired a toggle switch to the headlight circuit to feed power directly to the headlights, problem solved. plus i have daytime running lights if i wish. a soft short can also cause this problem
Did that Hemi, got a constant 13.5 even when revved up. No surge, the alternator has an internal diode, no external regulator. The headlight brackets are secure so vibration isn't the culprit, good leads though, thanks. I could see in your instance Stax where too many lights would overload the switch but I'm running 4 stock halogen sealed beams and turn/tail lights. No accessory lighting. I can see and older switch just not being up to the task, wear and tear, dust and so on causing that soft short you mentioned. Perhaps a resistance test at the switch might tell me something? which takes me back to Poncho's thoughts about the built in circuit breaker. I gotta dig through my stuff, between the Falcon and the Comet I probably have another switch around here somewhere.
I had a 1980 Zephyr years ago, the windshield leaked a bit and rusted the headlight switch. Coming down the 115 from Peterborough and the low beams started blinking on and off (car in front of me pulled over to the shoulder, musta thought I was a cop ... snicker snicker), changed the switch and all was good. Had another issue with headlights another time (different car), ended up being the floor mounted dimmer switch.
I have two more thoughts regarding this issue ... one being that I thought Halogen lights used more power than regular bulbs which could result in a overloaded switch. The other thought is this ... any chance your car is an ex-FBI undercover car and you somehow activated the "emergency" flashing headlight feature? If this is the case, look for a matte black switch just behind the .357 Magnum mounted under the dash, just behind the ashtray.
this past weekend, one of the cars at the show had blinkin headlights that switched from side to side. thats what i originally thought this post was about. anybody ever hear of this or did he really have malfunctioning lights.
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There are 106 miles to Chicago. We have a full tank of gas, half a pack of cigarettes, it's dark, and we're wearing sunglasses.
ive never heard of a headlight circuit being fused or having a circuit breaker, headlights are pretty vital and wouldnt be left to the care of a system that would shut them off. when your lights start blinking, touch the body of the headlight switch, mine would be so hot you couldnt hold onto it.
this past weekend, one of the cars at the show had blinkin headlights that switched from side to side. thats what i originally thought this post was about. anybody ever hear of this or did he really have malfunctioning lights.
If it's the car I think it is (yellow Ford coupe), the owner works in the movie industry and has access to suppliers of movie car equipment. Keep in mind though, alternating headlights are not legal here in Ontario, they are reserved for emergency vehicles only.
We had a 92 roadmaster wagon that had that wierd problem .When you turned the car on the daytime running lights would flash alternating from side to side like a cop car ,I actually thought it was an old cruser.There was also a loud clicking like a flasher unit only much more rapid .Dealer said it was some kind of modual and would cost $200+ so since all the lights worked and the flashing went away when we turned on the headlights that is the way it stayed till the motor went and we scraped it. Ed
If it's the car I think it is (yellow Ford coupe), the owner works in the movie industry and has access to suppliers of movie car equipment. Keep in mind though, alternating headlights are not legal here in Ontario, they are reserved for emergency vehicles only.
yes it was the yellow ford coupe.
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There are 106 miles to Chicago. We have a full tank of gas, half a pack of cigarettes, it's dark, and we're wearing sunglasses.
I had a 1980 Zephyr years ago, the windshield leaked a bit and rusted the headlight switch. Coming down the 115 from Peterborough and the low beams started blinking on and off (car in front of me pulled over to the shoulder, musta thought I was a cop ... snicker snicker), changed the switch and all was good. Had another issue with headlights another time (different car), ended up being the floor mounted dimmer switch.
I have two more thoughts regarding this issue ... one being that I thought Halogen lights used more power than regular bulbs which could result in a overloaded switch. The other thought is this ... any chance your car is an ex-FBI undercover car and you somehow activated the "emergency" flashing headlight feature? If this is the case, look for a matte black switch just behind the .357 Magnum mounted under the dash, just behind the ashtray.
I thought I'd found that switch......flipped it - the car disappeared. Wrong switch, I hit the "cloaking device". Took me three days to find the damn car.
Wolfman, the headlights are just off the shelf halogen sealed beams. You're right, they do draw more. The switch never heated up, no loose connections, replaced the floor switch, no luck. I told our oldest son about it and being an electrical engineer he put his thinkin' hat on. He installed a relay between the headlich switch and the headlights, increased the wire size and viola! nice bright steady headlights. I can spot a raccoon in an oak tree on the side of the road from 200 feet now. Thanks for your comments/suggestions.
your engineer son did more or less exactley what i did, supply alternate power to the headlights. im what you would call a paperless engineer, not documented
-- Edited by fatstax on Thursday 30th of August 2012 11:31:10 PM
Quite a common problem, especially with an older Ford headlight switch. The built in circuit breaker kicks out with 4 halogen lights on. Most wiring kits recommend the relay when upgrading to halogen lights, you have done the right fix! But I thought those roads around Jordan were too busy to run the highbeams anyway...............
Not when you're running the backroads Davy. Went out to a friends on Mohawk Point rd. yesterday, coming home on Feeder Canal was a whole different experience from prior.
Not sure if this will help but there is a difference between older and newer headlight switches and I am not sure which one your vehicle would have without looking at it. Modern headlight switches usually have at least two feed wires: one with direct battery power for the headlights that's protected by an internal circuit breaker within the switch, and another fuse box-protected wire for the rest of the light. Older headlight switches have only one input and no isolated headlight circuit. Instead, main-circuit protection is marginally provided by bimetallic strips inside the switch. One strip protects all the front lights (including the headlights and parking lights), while the other strip protects all the rear lights as well as the instrument-panel and interior lights. Similar to a carburetor choke's bimetallic spring, when a bimetallic strip heats up due to an increase in resistance, it expands and breaks contact with the terminals it controls, opening the circuit until it cools back down. Over time some of the bimetallic switches weaken and they will trip, shutting off the circuit until it cools. This causes "flashing" lights. If you can remove the headlight switch you'll see the terminals and the bimetallic switches. Simply bend the bracket so that it places slightly more tension against the contact points. Don't bend too much, a little a time until the lights no longer "flash". If you have an older style headlight switch this is a common problem and even replacing with another switch, even a new one, may not solve the problem but this little tweak should fix you right up. Hope this helps.
Thanks for the info ....Rob? So far it's worked really well with the larger wire and relay but at some point I'll have to pull the switch out again and when I do I'll give it a good looking over. We're going to change the Falcon over to an alternator shortly as well.
