i was running the car in driveway and i just figured id check the lights out before i get it inspected /68 chevelle by the way/i pulled out the headlamp switch and the car went dead i mean dead the car had no juice to even turn over .the battery is fine .so i shut the garage door and went upstairs till the next day .i went out to get in car and get more ****ed off and try to start it and guess what it started right up ./car isn't on the road yet / got any idea's on what to look for when i pull the light switch and the car shuts off again ? can a bad headlamp switch itself shut the car off ? any ideas would be great thank you .has any one heard of this ever happening?

Did you pull the switch out one notch or two?
How did you know the battery is "fine"?

What it the condition of the battery terminals and cable connections?

What you are describing is not a normal fault of a headlight switch. There is no way for a headlight switch being bad to cause the car to go dead. I woudl be very surprised if you are pulling the switch one notch (parking lights) and car dies. I might believe pulling two notches and the car dies because of an increased electrical load. Which goes back to the terminal issue.

I would probably try and get it to die again and then trace where you have power to and where not. That will highlight the offending connection.

Steve

thank you for your reply .i do pull the battery term's off when i don't run it for a couple days.and i thought the battery was fine because the next day it started right up .and its only 2 mths old and yes i pulled it out for the headlights /2 clicks / i bet ya that is my problem i'll clean them then reinstall them .sounds so simple when some one else figures it out , i must of had a brain fart.i should have known .if i do it again and it shuts off with the terminals clean for sure .I'LL BE BACK THANK YOU T/C is well worth the price to join and more

I would check the ground connections. Headlights don't draw enough to kill all power from the battery. If they did they would melt the headlight wiring harness.

Check the ground from the battery to the passenger side front fender. Check the mounting screws or ground strap from the voltage regulator to the radiator core support. Some voltage regulators have rubber insulators at the mounting screws and a separate ground strap. Some don't have the insulators and are grounded by the mounting screws.

Also check connections from battery to junction block, on the radiator core support behind the battery. From the junction block to the horn relay, driver's side of rad core support.

If they all look good check for corrosion at the end of the cable. The cable could be corroded inside the insulation, not obvious when looking at the cable.

If all look good and tight you're best bet is to use a volt meter to see where the voltage is being lost. Do these checks first, if you need further help post back and we'll go from there.

thank you very much for your help