My 64 Dart is doing strange things. If I turn on the headlights everything works perfectly including the high beams when you press the dimmer switch, including the indicator on the dash. Turn the key on and the turn signals work perfectly, right and left front and rear and the indicator lights on the dash work correctly as well. with the key on, turn on the left or right signal and it works fine until you turn on the headlights. with the headlights on, all the exterior lights work correctly but both turn signal indicators in the dash will flash and the high beam indicator also will flash. If you hit the dimmer switch, and turn on the left signal the right indicator light on the will flash, and if you put the right signal on. the left indicator will flash, but all the outside light work correctly. Checked all the grounds, traced the wires under the dash and hood. Can't find anything that looks wrong. Used multi-meter to check voltages and found nothing. This issue just started and I don't know why. Replaced headlight switch, dimmer switch and flasher. Can anybody help me? Please.
Electrical issues.
- Thread starter vpmopar
- Start date
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Unplugged the bulkhead connector under the hood and cleaned and checked all the wires in and out. Plugged it back in and no change. Have factory service manual and have gone though the schematics to trace wires until my eyes crossed. At wits end.
Quickly reading through, it sounds like crossed wires.
Those wires could be a filament in a dual filiment bulb or something like that.
Since you're willing to do some diagnotics, we should be able to help you find the cause.
Let's start with a circuit diagram.
From that we can see what is related.
When you turn the headlights on, current flows from the battery through the headlight switch and back to ground.
You'll have to tell us whether headlight position also turns on the front parking lights, but it does turn on the rear lights.
So that's situation 1. The ammeter should swing toward discharge to indicate the amount of current flowing out of the battery.
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Turning the headlights on also turns on parking lights. Turns on all taillights as well. I have disconnected the connector going to all rear lights with no affect on the issue. Ammeter gauge shows discharge when lights are turned on. Have replaced headlamp bulbs with no change.
OK good. I'll say a number of people here have found the front marker lamps on some pre-68 cars turn off when the headlights turn on.
This is simply the terminal the front lamp wires are connected to the headlight switch.
The headlight bulbs wouldn't be the cause of crossing with the turn signals.
The high beam indicator maybe a clue. We'll get to that. I don't show that schematic but we may have to add it.
Signal circuits are a little more complicated.
next situation.
Turning the key on connects power to the run and accessory feeds. Run is ignition and alternator. Accessory is everything else.
Finally, lets look at the turn signal and indicator wiring and see if we can figure out what would work normally with the headlights off but get a backfeed with the headlight on.
I don't have a '64 shop manual, so if you do, that will help.
Whenever things like this happen and it doesn’t make sense, it is often a ground issue. When things are back feeding through places that would normally be grounded, it gets very confusing.
Sounds like you could be missing a dash ground. I am not familiar with a 64, but on 67-68 there are at least three different ground paths on the instrument cluster circuit board, and a ground from the metal instrument cluster frame to the dash frame.
Sounds like you could be missing a dash ground. I am not familiar with a 64, but on 67-68 there are at least three different ground paths on the instrument cluster circuit board, and a ground from the metal instrument cluster frame to the dash frame.
slantsixdan
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That's not how it's supposed to work. With very few exceptions (not including the '64 Dart), pre-1968 cars turn the parking lights on only at the first click of the headlight switch. Pull to the second click and the headlamps come on but the parking lights go off. For '68, one of the new federal safety standards was for lighting, and one of its requirements was that the parking lights stay lit with the headlamps (so other drivers can still see your car's width if a headlight burns out). Making this upgrade deliberately is a good idea and it's not difficult, but that's beside the point at the moment; if your parking lights stay lit when you pull the headlight switch to the second click on a '64 Dart that hasn't been deliberately upgraded to do so, it's a pretty good indication you've got a crossed wire somewhere.
That said, you've got four very likely candidates for the source of the trouble, one at each corner of the car, in the form of the double-filament bulbs used for the park/turn and tail/brake lights. If there is a faulty or inadequate ground at any of these four sockets, current will take unauthorised paths. The parking/tail light circuit includes the dashboard lights, and the turn signal circuit includes the dashboard turn signal pilot lights, so there are easy chances for the kind of mayhem you describe if current gets going the wrong ways along the wrong paths.
Another kind of trouble that can happen at those four locations is that the major (bright) and minor (dim) filaments in the bulb can touch. They're not supposed to, and if they do, that'll bridge two circuits that aren't supposed to be bridged. A variant form of this fault is if someone crams a single-filament bulb where a double-filament bulb is supposed to go. Nominally it won't fit, but it happens often enough, and then the single central contact on the bottom of the bulb can bridge the two side-by-side contacts in the socket.
So check for a good ground at all four corners, and toss in four new bulbs—give the old sockets an assist by getting the bulbs with the bigger crescent-shaped base contacts and the noncorroding nickel-plated base, that's these or these (also available locally).
Also, as has been mentioned, you'll want to check for a proper instrument cluster ground.
Lets follow the rest of the path here. This is based on '67 with the hazzard switch removed.
Using the left turn signal as an example. Current flows to the flasher, then to the column connector and up to the turn signal switch.
The switch connects the rear front turn signal lamp seperately. This is because stepping on the brake will overide the rear turn signal.
Here's where the problem is. So lets break it up.
This does not happen with the parking lights on alone?
If so, then its related to the headlight circuit.
If it happens with parking lights on alone, then its parking/tail light circuit related.
The fact that both indicators are blinking means power isn't flowing through the turn switch but is finding a short cut.
Also, to get the indicators to blink, power must be flowing through the flasher.
Since the high beam indicator is blinking too, even on low beam, something must be connecting it to the turn signals.
Do the turn signals respond at all with the headlights on low beam?
FWIW. On '67 Barracuda, the high beam indicator wire comes from the bulkhead high beam terminal.
All 67 Barracudas were wired with parking lights that remained on with the headlights on.
If in these statements you are telling us the exterior lamps work as expected, not flashing on headlight low, and blinking the correct direction when the high beams are on, then the problem is someplace where just the turn and high beam indicator lamps could be seperately effected from the rest.
Probably at the dash itself, slight chance at the column connector.
I have been out working on this problem with your suggestions and drawings. Looking for a disconnected ground that I may have missed. I will continue to look until i get it right. Thanks for everyones comments. I will update as soon as I have some thing to report.
Refering to my comment to Dan? My point was that 'very rare' doesn't mean its correct or incorrect for the OP's particular car. Its just a generalization.
Here's a sketch that includes high beam indicator. I don't know if the connection locations or colors are the same as on your car.
After Dan's comments and thinking further, I really think its worth checking if the issue shows up with the switch in Park as well as in Headlights.
Another thing to do is to take out lamps one at a time.
67Dart273
Well-Known Member
I THINK YOUR INSTRUMENT CLUSTER IS POORLY GROUNDED
67Dart273 you are correct! Bad ground in the connector to the printed circuit board on the instrument cluster. Put in a wire off of one of the screws that went to the ground terminal and fastened it to a good ground. Everything works perfectly and my dash lights look a little brighter. Thanks to everyone for all your help. Electrical issues are a major pain! Thanks again!
slantsixdan
=..=
OP's car is a '64 Dart. '64 Darts did not come with parking lamps wired to remain lit with headlamps; that was limited to Barracudas til '68 when it spread to all cars. This is all plain facts; no guesses or assumptions required. The problem at hand is complicated enough without introducing spurious variables.
All you had to do was say that in the first place.
All of which is irrelevant since Del figured out the most likely source of the problem faster than either of us.
I should have stuck with post 11, LOL.
He did. He outlined it very well in post #8.
You are correct that Dan did put 64 Dart parentises in post 8.
As far as what he outlined, that the problem was most likely in one of the four dual filament lamps or bumbs, that was a swing and a miss. Del got it in one shot.
I think Del picked up on the fact that only the instrument panel indicator lights were doing odd things, not the exterior signal lamps.
The bad ground wouldda been my guess too, as I've seen it make the turn signal indicators come on like that. Normally when I see that, a ground (or lack thereof) comes to mind.
.......but he's Del. what do you expect? He's a genius. lol
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