electrical and ignition Headlights Not Working....

[Robotin]

so..... my headlights were working fine for a long time.... one day i went in my car. turned them on..... and nothing. nothing on my hazards either. my turn signal/running lights work. and IIRC my brake on lights arent working either...

 

 

i replaced the front sealed beams. still nothing. went and followed the wires from the headlight all the way to dash, so i took my cluster out to make sure they had good contact with the switch. all seemed fine...

 

 

fuses are all fine as well. not really sure where else to check...

 

 

[Hans]

You might check the common ground for these  - many brown wires attached to inside fender I believe. but the side lights ground there too... I'd check anyway. Also try cleaning the fuse holders with fine emery paper and using new fuses.

[Robotin]

i put a voltmeter on the ground and positive terms when i had to headlight switch pulled out. and it read 0. i will check the ground next time i look at it. my concern is i did not touch the headlight wiring AT ALL!! so i thought it was strange they just stop working out of no where.

[Chamonix72]

Start cheap and easy. Fuses?

[Mike Self]

Since you have a '72, the headlights are wired through the ignition so that when you turn the ign off, the headlights go off but not the parking lights or tail lights.  So, if your parking/tail lights are still working but not headlights, I'd check the wiring at the ign switch to see if it's feeding the "ign on only" side of the headlight switch.  Look for the green wires at terminal 15 on the ign switch.  They should be hot with the ign on.  Then go to terminal 30 on the headlight switch.  It should be hot with the ign on, but not with the ign off.  If all that checks out, then I'd start looking at the dimmer switch.  They don't go bad often, but they've been known to, and both low and high beam feeds go through it.

 

Also, on a '72, the low beams are fused, but not the high beams.  So if the low beams don't work but the high beams do, I'd suspect the relevant fuses.  If neither  work, then I'd go back to the feed from the ign switch.

 

mike

Edited January 15, 2014 by mike

[Roundeie]

When I bought my car my dip switch was bad and had to be replaced to make the headlights work.

[Robotin]

i dont have a 72. i have a 70. the fuses look fin. but i might replace them all anyway, (i mean theres only 6).

[Hans]

I, ve had bad fuses that looked fine. Be sure to clean the tabs. I, d still clean up grounds.

[Chamonix72]

I second your fuses looking fine but being bad. One of my headlights kept going out, and that stopped as soon as I changed the fuse.

[jp02ti]

jiggle the high-low switch.  flash the lights, flip it to high and then back to low.  the little bits inside get sticky and don't always go back where they should.

headlights aren't fused on a '70.

[Hans]

Did they have a relay?

[AustrianVespaGuy]

I think even the old roundies used relays in the headlight circuits, but if they're like the later squaries, it's in a really, really dumb way where all of the high current STILL goes through either the ignition or the headlight switch.  I recently redid the wiring for all of the relays on my '75, both to add in Megasquirt and to also fix some of these oddities.  My wiring diagram is attached for your reference.  Ignore the wire colors, but I fuse #s and the switches are on there, so should help you to fairly easily rewire your headlight relays 'properly' which should lead your to determining and fixing your current problem, and then prevent it from happening again in the future.  HTH!

Relay_wiring.pdf

-Carl

[Hans]

2002tii webpage has wiring diagrams. Looks like yours has a ground for just the headlights. I'd start there.

 

 

 

[Robotin]

so today i took my volt meter and check the connector again.... still 0. then i check my headight switch. and it reads 12v... so its somwhere in between there... i might just wire in my headlights to my turnsignal/running lights. but i rather find out whats wrong....

[Hans]

I think the steering column stalk is between the two. Check the wiring diagram