73 Dart No Headlights, Turn Signals, Brake Lights, or Parking Lights
- Thread starter Jack11211
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PRC
Well-Known Member
Check your headlight switch. If I’m not mistaken, power to each of those runs through that switch.
Two different circuits. One is battery, other is ignition.
I recently had the same thing happen to me. Exactly same symptoms and also a 73 dart. It was a bad headlight switch.
Thank you all for your input. I bought a new headlight Switch and it is coming in on Thursday. I'll keep you posted with how that works.
What does the 'alternator' gage do since you change the hazzard or turn signal flasher unit?
That gage is an ammeter. It's shows whether the battery is discharging or charging.
When the engine is running, it should indicate either battery charging or be centered.
If it the battery is discharging while you are driving, then something is wrong with the alternator or its wiring.
2. Then with these clues look at the general circuit scheme to see what the dead ones have in common.
I'll post a generic scheme here. You'll may have to look at the shop manual diagrams to verify and fill in the details.
The basics of the wiring are this:
With the engine off, the only power source is the battery.
The dome light draws power though the 'always hot' portion of the fuse box.
The parking lights, brake lights and hazard also draw power through the 'always hot portion of the fuse box.
Check a '73 shop manual or owners manual for which ones share a fuse.
The headlight switch has two connections to the main splice.
Power for the headlights does not come through the fuse box. Instead there is an internal circuit breaker.
'73 Dodge FSM shows the hazzard and stop lights get power from the same circuit as the dome. Verify that if you can but testing all of those things will narrow down where the problem(s) are.
edit: And Tooljunkie is correct in that the turn signals only get power when the key is switch on. So they get power from the 'accessory' feed to the fuse box and are on different fuse (not shown in the sketch above).
If power is not getting to a light, then there is a break in the circuitry or possibly a short (two wires touching in a way that provides an easier path to ground).
If an item doesn't turn on but the ammeter moves to discharge, then suspect a short.
An break or corrosion can be on the ground connections too.
That gage is an ammeter. It's shows whether the battery is discharging or charging.
When the engine is running, it should indicate either battery charging or be centered.
If it the battery is discharging while you are driving, then something is wrong with the alternator or its wiring.
1. Check what other electric circuits are working or are dead.
2. Then with these clues look at the general circuit scheme to see what the dead ones have in common.
I'll post a generic scheme here. You'll may have to look at the shop manual diagrams to verify and fill in the details.
The basics of the wiring are this:
With the engine off, the only power source is the battery.
The dome light draws power though the 'always hot' portion of the fuse box.
The parking lights, brake lights and hazard also draw power through the 'always hot portion of the fuse box.
Check a '73 shop manual or owners manual for which ones share a fuse.
The headlight switch has two connections to the main splice.
Power for the headlights does not come through the fuse box. Instead there is an internal circuit breaker.
'73 Dodge FSM shows the hazzard and stop lights get power from the same circuit as the dome. Verify that if you can but testing all of those things will narrow down where the problem(s) are.
edit: And Tooljunkie is correct in that the turn signals only get power when the key is switch on. So they get power from the 'accessory' feed to the fuse box and are on different fuse (not shown in the sketch above).
If power is not getting to a light, then there is a break in the circuitry or possibly a short (two wires touching in a way that provides an easier path to ground).
If an item doesn't turn on but the ammeter moves to discharge, then suspect a short.
An break or corrosion can be on the ground connections too.
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67Dart273
Well-Known Member
Some of you are full of crap. Headlight switch in a Mopar has nothing to do with brake, signal lights. Only trail/ park and headlights. If there is something like a grounding problem at a lamp then it can lead you down a false road.
All interior power comes off the big welded splice in the black ammeter wire. This branches off and feeds headlights only power to the headlight switch, feeds the "hot" buss in the fuse panel, feeds the input to the ignition switch, and goes back out through the bulkhead to the alternator
The tail/ park lamps are not feed off headlights circuit. They come from a fuse in the panel off the hot buss
Brake and signal are both fed by fuses in the panel. Brake lamps are fed by a fuse off the hot buss, the signal lamps fed by another fuse fed by the ignition switch.
You have THREE major separate distinct circuits here.
All interior power comes off the big welded splice in the black ammeter wire. This branches off and feeds headlights only power to the headlight switch, feeds the "hot" buss in the fuse panel, feeds the input to the ignition switch, and goes back out through the bulkhead to the alternator
The tail/ park lamps are not feed off headlights circuit. They come from a fuse in the panel off the hot buss
Brake and signal are both fed by fuses in the panel. Brake lamps are fed by a fuse off the hot buss, the signal lamps fed by another fuse fed by the ignition switch.
You have THREE major separate distinct circuits here.
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