Headlight switch

[buckethead]

My understanding is that when I pull out the knob on the headlight switch the headlights should pop up and the lights should come on. I get lights but no pop up. They will pop up using the other knob under the dash. How are the vaccuum lines tied into the light switch and what should I look for to remedy this situation..:confused Thanks for your help

 

[paintdaddy]

There are two vacuum lines that run to the headlight switch.One comes from the firewall and the other comes from that lower switch.Check to make sure they are all hooked up.To see the headlight switch you might be able to remove the screw on the side of the dash and look in there with a flashlight.

 

[69MyWay]

Did you buy the car this way, or did the problem just develop?

If you bought it this way, my guess is the prior mechanic simply plugged them off because the headlight switch was leaking.

If you disconnect them, the lights will default to up. That is what tells me yours if plugged, or your headlight switch is hanging up on the valve inside and not letting them through.

 

[Bob Chadwick]

My recollection is that if they are hooked up backwards on the light switch they will do the same thing.

 

[vmrod]

The tubes may be reversed on the light switch side. While the car is running, pull the light switch on and listen carefully. If the switch was tubed oppositely, then you may hear a hissing sound (from the light switch) when the lights are turned on.

(with engine running) Turn on the light switch. Does anything happen? Turn on override switch. (the switch under the dash). Did anything happen? Now, close the override switch. Did the lights close, or did they stay open? If they stayed open, or closed very, very slowly, I would suspect that the tubes are reversed on the headlight switch.

To aid in troubleshooting, remove the 2 tubes that connect to that switch under the dashboard. (It will not matter if your light switch is on or not.) Also, remember where the tubes go.

If your headlights pop up, then you can reconnect the tubes as they were, and check out the headlight switch. Try reversing the tubes on the headlight switch, and see what happens. This is likely where your problem is.

-Vic

 

[igasper10]

74' Vette

I have a 74' L48 project. I'm having headlight problems as well. I've noticed a "mystery" silver switch under my dash on the driver's side. Is this an override switch? Or was that not added until 76'?

Ian - ;help

 

[Bob Chadwick]

I think they all had them to get the headlight up without turning the lights on.

 

[igasper10]

I think they all had them to get the headlight up without turning the lights on.

A dumb question, but how does it operate? Is it a push/pull type switch or what?

 

[vmrod]

yes. pull the switch down and the headlights should pop up. push to close. (or was it the other way around?) But anyway...it is a pull/push operation.

I have a simple vaccuum schematic here. Perhaps today or tomorrow, I can draw it up nicely and post it.

-Vic

 

[Bob Chadwick]

Under vacuum

 

[vmrod]

Bob here's another one of my diagrams. It shows which ports do what on the switches and relays.

If you find it helpful, you are more than welcome to put it on your website for others to use. (always for free)

Your website is becoming a valuable place for corvette information!

-Vic

 

[Bob Chadwick]

Thanks Vic. I try to help where I can. I know this place is a wealth of information and I try to give what I get.

The information is up and on this website under headlight circuit.

Bob

 

[buckethead]

Hey thanks for the info on my light problem. Gives me some ideas on what I need to look at. I am totally confused by all those vaccuum lines. Speaking of confused, I just got back on line ...had some computer problems so wasn't able to check the forum for responses. Thanks again

Doug

 

[vmrod]

Bob,
I didn't see the heading 'Headlight Circuit'. Did you add it recently?

Doug (Buckethead),
don't get too overwhelmed by all of those vaccuum lines. They are really not that bad. If you really want to get intimate with your car, then open up the hood and trace every vaccuum line. Make sketches and stuff. I believe that Bobchad has all control-vaccuum line diagrams on his site. (I'm not sure about carbeurator vaccuum lines, but that is another story.) If you take your time, you'll figure it out. Besides, someone is usually around at this website for guidance too.

-Vic

 

[Bob Chadwick]

Added it last night. The last URL under the red Vacuum heading.

 

[vmrod]

Coolatious! I just needed to refresh the page.

Did you understand the schematic? What about the instructions for testing the ports on the switches? I wanted to be able to make a diagram that would be easy for someone to understand how the system works.

The diagram may look a little complicated with the symbols that I used, but all of those 'C', 'NC', and 'NO' are important items to determine how things should tube-up.

I could always show it like an electrical schematic, but I'm afraid that would confuse people even more. What do you think about it?

-Vic