head-lite dimmed

[BUXMAN66]

the pass. side head light has it's own ground at the core support,correct? so,shouldn't the driver's side be grounded out by itself also? my driver's side headlight is real dim which leads me to believe that i don't have a good ground or??? when i changed over my old external voltage regulator i clipped the wires that led to it and also from it and thinking that the black wire coming from the v.r. was a ground(it went to the v.r.) i clipped it also.so.........was the ground for the driver's side headlight routed through the voltage reg.? i tried to jump a wire from the ground prong of the headlight to the washer bottle holder bracket and didn't notice a difference. (late at nite after work 2nd shifter) guess i'd better do it in daytime, but am i on track?

[Hooter]

Sounds like you are having a grounding problem. Now when I took the wiring harness apart on my 69 both headlights were grounded at the same place. A bolt on the passenger side behind the battery on the firewall.

[JimKshortstep4x4]

I doubt if you cut the ground to the headlight because of the way it is made. I would check the connection at the headlight. Clean it and try wiggling it to make contact.

Jim

[70c10]

The ground goes to the regulator, alternator and sheet metal according to the diagram.

[Capitol68]

mine does that sometimes, it is usually the connection on bulb. If im at a place i cant pop hood i can bump the bulb with my hand and it usually works. clean contacts

[BUXMAN66]

thanks, guys i'm heading out ot the garage now to take a looksie. so there's only one ground for the 2 head lights?i thought each light was individually grounded on it's own.

[COBALT]

It may be a "weak" ground or an untrue ground.

Light brightness is a function of voltage. If two bulbs are in series the bulbs will get dimmer the more bulbs you add to the circuit, but if they're in parallel they stay the same brightness with 1/2 the current, and less current the more bulbs you add.

I would look hard in how many elements are recieving power on the same hot, and whether or not they all point to the same ground. I bet they don't. They should each be on their own dedicated "true" ground to recieve the complete 12 volts. Use a volt meter to determine the voltage to that headlight. If it's not ~12V then you're not getting complete voltage to the bulb. Use the engine block or the frame as a true ground, and see if there's a voltage reading between the block or frame, and what you THINK is the ground to the headlight. I almost guarantee that you'll get a reading, which means that headlight ground isn't really a ground at all.

The inverse of this is also true. That ground may be "true", but the voltage supplied by the hot isn't 12 volts. That's why you need to check the hot lead to determine that. Shouldn't both headlights be on the same hot? If so they'll be the same brightness.

If all of this pans out, and it's still dim try switching the headlights and see if any bulb in the same position is dim. If so then you've got a head-scratcher. If not then it's the bulb.

Good luck.

[70c10]

You are correct. Each light has a seperate ground.

[BUXMAN66]

gotcha!went out and looked at it and come to find out the driver's side headlite is grounded out thru the voltage regulator,rehooked up the ground coming from the v.r. and it works great now!(i had changed the alt. to a 1 wire)thanks,everyone!