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Weird light problem....70 charger

Dano65

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Oct 30, 2017
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Location
Gary, Indiana
I'm working on a 70 Charger with a problem I've never dealt with before. The driving/tail lights stay on all the time? Headlights turn on/off like they should but the others don't? Tried a new switch but it's doing the same thing? Any ideas?
 
Are they staying on even when the key is off? The more info you can tell us, the better it'll be to diagnose it.....
 
Im with dadsbee.. sounds like the brake light switch is on the blink...
 
I would try unplugging the column harness and see if the signal switch or hazard switch is stuck somehow.
 
Sorry for the delay, yes front and rear lights stay on even with the key off. Have to disconnect the battery. Original harness. Brake lights are fine, just the running/tail lights stay on all the time. Just started doing this all of a sudden that's why I figured it was the switch. Thanks for the replies.
 
Any ideas? Or suggestions that I can try?
start by removing 1 fuse at a time this might show what circuit is shorted to power. if that doesn't work then unhook power at the starter relay 1 at a time this should show witch power is supplying the light circuit then with a wire diagram to see what could supplying power to running lights. as said hear could be turn signal switch. buy the wiring diagram as dccoronet said, i would unplug this first. if the pink and black are touching it could have power all the time as the pink is power all the time .
 
Past what DCCoronet suggested, could be shorted to a non switched power wire.
In other words, it's getting power all the time...find out why.

The driving/tail lights stay on all the time?
Okay. It would help if you have wiring diagrams for the car. Look at the circuits for both driving and tail lights...they will join, via the wiring, somewhere. One place to be sure to check is, the fuse box wiring, since both switched, and non-switched wiring feeds go through there.
Many of those wiring circuits will have connection 'blocks', to separate different wiring harnesses. Pick a spot (connection block), pull it apart, and see if there's any changes. 'Somewhere', probably before the circuit splits front to rear, is where you'll find a shorted wire.
 
Suggest using a test light, and know which wires to test, in that circuit. You'll get it figured out!
 
Any ideas? Or suggestions that I can try?
The 1970 Charger headlight switch is different from the other years. There is also a relay under the dash that is connected to it. Try disconnecting BOTH, cleaning the terminals and wire ends and connecting it back up.
 
Sounds like the power wire for the running lights is energized - it is the black wire coming off the headlight switch - turn the switch off and then use a multimeter and see if it is... Then unplug the light switch and test again - If it still has power (the now disconnected wire) it is picking up power somewhere - go over the wiring and see if anything is obviously arching - not a huge electrical guy but there is a diode in the wiring that - if it became fused, would energize the black wire off your headlight switch which would light up your running lights... remove the diode and see if it stops
 
I was messing with it today and will try your latest suggestions tomorrow but I did find that the lights are not getting full 12v when the switch is off cause they're pretty dim when off but normal brightness when they're switched on. And I found that it's the thick black wire that comes off the right side of the bulkhead connector and goes to the starter relay. That must power it all cause when I disconnect it the lights go off completely. Man, how I hate electrical problems :(
 
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