Question on 1966 Corvette Interior Lighting

[Larry E.]

Restoring a 1966 Coupe. We know when the light switch is turned all the way to the left. (Counter Clockwise)the courtesy
lights are turned on. Question>Should the Dome light also turn on? I assume this works even when the key is in the "off"
position. Correct? I also assume(sometimes bad) that when one of the light bulbs burn out the other ones should work.
Correct? All the bulbs are #90's. (Twin Contacts) Thanks in advance>Larry

[Leif A.]

Re: Question on 1966 Corvette Interior Lighting

Everything you assume, Larry, is correct!

[Larry E.]

Re: Question on 1966 Corvette Interior Lighting

Thanks Lief for the response. Now my next question>Lights work when the light switch is turned all the way counter-clockwise. When
I turn it clockwise the lights go off which they should. Here is the catch>lights will not go on when I open either door. Wiggled the door
switches with no luck. What could cause this to happen?? Thanks Again-Larry P.S. Would the light switch and the door switches have
separate circuits going to the courtesy lights??

[Larry E.]

Re: Question on 1966 Corvette Interior Lighting

Anybody? Need help. Could it be in one of the electric junction connector boxes?(Like the ones on the firewall) Thinking we may
have to clean the connectors. If so where physically would this be on the 66?(For the door switch to the courtesy light) Thanks-Larry

[Bill S.]

Re: Question on 1966 Corvette Interior Lighting

The courtesy lights work through the ground. The lights have power to them all the time, the door switch provides the ground. Start at the switch and see if you have 12V. If you do then the switch is bad, if no 12V the problem is upstream. If both doors are not working at the switch more than likely the problem at fuse block or a connector.

[Edward D.]

Re: Question on 1966 Corvette Interior Lighting

Larry, you have a ground problem, not a power problem since courtesy lights work when using the light switch which makes the ground. The door switches ground to the birdcage, your problem could either be bad switches, wire (its a white wire), or birdcage grounding. To check, pull a switch and attach a jumper to wire bullet connector and a known good ground (the steering column bracket for instance). Lights go on? If so you have either a bad switch or bad ground to the birdcage. If not then check the wire for cuts or breaks. Easy way to do this is turn the courtesy lights on using the light switch, that will connect the entire white wire circuit to ground, then check that the wire bullet terminal at the switch has continuity to ground. If it doesn't you have a wire short, cut or broken somewhere between the bullet connectors and the splice where the courtesy light ground circuit comes together, see your wiring diagram. Check birdcage continuity to ground at the switch threads using a continuity tester. There should be a ground strap under the car at the front of the birdcage to the frame, make sure this is there. I see a lot of bad switches, remove them and test that they make continuity from the back terminal to the outside nut when the pin is out and break continuity when it is depressed. Test methodically and you will find the problem.

[Larry E.]

Re: Question on 1966 Corvette Interior Lighting

Thanks to all the responses; will continue to fix the problem>Larry

[Larry E.]

Re: Question on 1966 Corvette Interior Lighting

[QUOTE=Edward Dupere (60605);857159]Larry, you have a ground problem, not a power problem since courtesy lights work when using the light switch which makes the ground. There should be a ground strap under the car at the front of the birdcage to the frame, make sure this is there.

Ed:Thanks for the idea's. Can you or anybody else tell me exactly where this ground strap should be? Anybody with a picture would be helpful. Is there only one or one on each side? There seems
to be a lot of ground straps missing on this 53 year old girl. Larry

[Larry E.]

Re: Question on 1966 Corvette Interior Lighting

Ok; found a picture for it(Ground Strap to Birdcage) on an old post that applies to the 1967. I assume it would apply to the
1966 as well. If not please correct me. Where would this be under the car? eg. around the start of the bell housing perhaps?
Would there be two of them(one for each side)? Larry

[Edward D.]

Re: Question on 1966 Corvette Interior Lighting

Drivers side, outboard, just to the rear of the small triangular splash plate. Right at the front body mount bracket at the bend in the frame.
Did you try to jumper a switch to ground yet? Just use a 7/16 deep socket and unscrew a door jamb switch. Pull forward but don't disconnect. Put a jumper wire clip on the back wire connection, clip the other end of the jumper to the pedals bracket. Lights should go on, if they do not the problem is in the wiring.

[Larry E.]

Re: Question on 1966 Corvette Interior Lighting

[QUOTE=Edward Dupere (60605);857215]Drivers side, outboard, just to the rear of the small triangular splash plate. Right at the front body mount bracket at the bend in the frame.
Did you try to jumper a switch to ground yet?

Ed>Not yet. I know there is no ground strap in that area above. Will put a jumper cable there to ground the birdcage and try the lights. If it
does not work will go to the switch then. Thanks-Larry

[Larry E.]

Re: Question on 1966 Corvette Interior Lighting

Drivers side, outboard, just to the rear of the small triangular splash plate. Right at the front body mount bracket at the bend in the frame.
Did you try to jumper a switch to ground yet? Just use a 7/16 deep socket and unscrew a door jamb switch. Pull forward but don't disconnect. Put a jumper wire clip on the back wire connection, clip the other end of the jumper to the pedals bracket. Lights should go on, if they do not the problem is in the wiring.

Ed>Update of this problem>Ok;pulled the Drivers side switch and grounded the wire and lights went on. Easy fix>installed new
switch and everything OK. Sounds simple;now to the Passenger side>Pulled switch and was surprised the white wire that was
attached to the switch was only 5" in length. Someone cut the wire years ago when a burglar alarm was installed. (Don't ask me
why they cut this wire). So my plan of attack is to solder a longer white wire to the short white wire(since it has the proper connector on) and connect it to the new door switch. Since I do not know where the group of ground wires(20W)are physically(See AIM) I
plan to splice this into the courtesy lamp socket black wire which is the ground wire. The other wire is orange (the positive) which is on all the time. I'll try to splice this in where no one can see it. Sounds good?? Comments. Thanks in advance.Larry

[Edward D.]

Re: Question on 1966 Corvette Interior Lighting

Larry,
No, that is a bad plan. The white wire ground circuit is not always connected to ground. When you close the door switch (by opening door) it connects the white wire circuit to ground, this in turn supplies a ground to all of the courtesy lights and they go on. So, all you should do is lengthen the shortened white wire to the switch and reconnect it from harness to the switch. Then your courtesy light circuit should work as designed.

[Larry E.]

Re: Question on 1966 Corvette Interior Lighting

Ed: Thanks again for helping me. I make some comments under yours.
QUOTE=Edward Dupere (60605);858657]Larry,
No, that is a bad plan. The white wire ground circuit is not always connected to ground.

IT WON'T BE; JUST WHEN THE DOOR IS OPEN. WHEN DOOR IS CLOSED NO GROUND WILL BE SENT. AFAIK>THIS WOULD BE THE SAME "ELECTRICAL POINT AS ORIGINAL SINCE THE BLACK WIRE ON THE SWITCH GOES TO THE
GROUP OF GROUND WIRES CONNECTED SOMEWHERE IN THE HARNESS AS SHOWN IN THE AIM.

When you close the door switch (by opening door) it connects the white wire circuit to ground, this in turn supplies a ground to all of the courtesy lights and they go on. So, all you should do is lengthen the shortened white wire to the switch and reconnect it from harness to the switch. Then your courtesy light circuit should work as designed.[/QUOTE]

NICE IDEA BUT AS THE AIM SHOWS THIS POINT IS EMBEDDED IN THE HARNESS SOMEWHERE;BUT WHERE? DO NOT
KNOW WHERE THIS POINT IS. I DOING THE SAME THING AS FAR AS ELECTRIC CIRCUIT KNOWS.
WHERE AM I GOING WRONG WITH THIS IDEA? ANYBODY?? LARRY P.S. SHOULD HAVE NOTED THAT I CAN NOT
FIND THE LONGER WHITE WIRE (WHERE CUT) THAT GOES TO THE GROUP OF GROUND WIRES. THINKING IT WAS
USED WITH THE BURGLAR THAT WAS INSTALLED YEARS AGO AND SINCE HAS BEEN TAKEN OUT BY PREVIOUS
OWNERS.

[Edward D.]

Re: Question on 1966 Corvette Interior Lighting

Larry,
The two wires at your passenger side courtesy light socket should be white (ground circuit) and orange (hot). If the ground is black someone probably replaced the socket at some time. If the light goes on when you open the drivers door or turn the light switch knob all the way left then your black wire is spliced correctly into white wire ground circuit. Splicing your passenger side door switch into that wire should work OK. It will provide the contact to ground for the entire white wire courtesy ground circuit when the door is opened and all your courtesy lights & dome light should go on.