Testing a 69 headlight switch pin-outs?
Thread Starter
Burning Brakes
Joined: Dec 2008
Posts: 971
Likes: 45
From: Middlesex NJ
Testing a 69 headlight switch pin-outs?
Guys
New wiring New switch.... no 12v to the dash lights.
If I apply 12v to the green wire at the headlight switch harness (switch removed) the dash lights work... I have 12v at the red wire all the time.
So that tests the harness,
fuse panel and fuse
and the grey wires out to the bulbs
and that I have a good ground for the bulbs to get to.
I have tested it both with the switch 1 dent out and 2 dents out and varying the rheostat.
I cannot figure out how this switch works... or I have two bad switches (old and new one). I know the 12v (meter tested) is at the red wire in the harness and its there all the time with or without the key as that is the same red wire that feeds the ignition switch.
I simply cannot get any voltage (or show any varying resistance between the red terminal and green terminal on the switch) between the Red wire and the terminal that goes to the green wire that goes down to the fuse panel!!! (again 12v direct to the green wire and my dash lights work) I just get nothing from the terminal that goes to the green wire when I hook the harness to the switch (again I have 12v at the red wire).
What am I missing? Does anyone have a pinout diagram as to how the dash light dimmer circuit is configured in the switch.
I am expecting to get varying voltage out of the green wire to dim or brighten the dash bulbs.
New wiring New switch.... no 12v to the dash lights.
If I apply 12v to the green wire at the headlight switch harness (switch removed) the dash lights work... I have 12v at the red wire all the time.
So that tests the harness,
fuse panel and fuse
and the grey wires out to the bulbs
and that I have a good ground for the bulbs to get to.
I have tested it both with the switch 1 dent out and 2 dents out and varying the rheostat.
I cannot figure out how this switch works... or I have two bad switches (old and new one). I know the 12v (meter tested) is at the red wire in the harness and its there all the time with or without the key as that is the same red wire that feeds the ignition switch.
I simply cannot get any voltage (or show any varying resistance between the red terminal and green terminal on the switch) between the Red wire and the terminal that goes to the green wire that goes down to the fuse panel!!! (again 12v direct to the green wire and my dash lights work) I just get nothing from the terminal that goes to the green wire when I hook the harness to the switch (again I have 12v at the red wire).
What am I missing? Does anyone have a pinout diagram as to how the dash light dimmer circuit is configured in the switch.
I am expecting to get varying voltage out of the green wire to dim or brighten the dash bulbs.
Thread Starter
Burning Brakes
Joined: Dec 2008
Posts: 971
Likes: 45
From: Middlesex NJ
Ok I figured it out...
Well the red 12v wire from the ignition switch is not the only supply coming to the headlight switch.
Turns out that the orange wire in the headlight switch connector carries 12v as well it's used to supply voltage to the tail lamps and guess what that's tied to at the headlight switch ... One side of the rheostat!!!!! I had my tail lamp fuse out so no power to the orange wire so now power to the dash lights. Can't believe that.
The headlight switch has a thin brass jumper at the base of the contacts to supply the 12v from the orange wire to the one side of the rheostat . The other end of the rheostat goes to the green wire for the dash lights.
There is no internal contact inside the switch for the rheostat it's all external. I had to take my switch apart to figure this out.
Hope this helps someone else.
Well the red 12v wire from the ignition switch is not the only supply coming to the headlight switch.
Turns out that the orange wire in the headlight switch connector carries 12v as well it's used to supply voltage to the tail lamps and guess what that's tied to at the headlight switch ... One side of the rheostat!!!!! I had my tail lamp fuse out so no power to the orange wire so now power to the dash lights. Can't believe that.
The headlight switch has a thin brass jumper at the base of the contacts to supply the 12v from the orange wire to the one side of the rheostat . The other end of the rheostat goes to the green wire for the dash lights.
There is no internal contact inside the switch for the rheostat it's all external. I had to take my switch apart to figure this out.
Hope this helps someone else.
