Got in my vette, pulled headlight switch and the following happened...

No Dash Lights
No Gauge Lights
No taillights
No side marker lights-Front or rear
but
headlights work
Directionals work
Brake lights work
Hazards work
courtesy lights work

All fuses check ok. I suspect a ground is lost but not sure where to look.
I had problems earlier where the right turn signal indicator was on steady when lights were on but would blink when right turn signal was used. I finally installed new headlight switch that was working fine and now this has happened.
I'm down to my last 3 hairs on my head.
Help !!

 

okay. I pulled those last the hairs from my head in frustration. Hope the wife likes the bald look.

 

Hope your hair grows back see post dated 3-18-06 by labulldog (unusual elect.problem) His problem solved . It sounds related to your problem. good luck

 

that I made on powerpoint off to the left here:
<<----
in my corvette pics;

Mine is a 68 and to the best of my understand the light switch is wired as shown. Perhaps this my help you.

 

you may have blown 2 fuses, the one for the parking/marker lamps and the separate fuse to the console lamps.

It could be a ground problem also, but I'd check the fuses first.

 

I don't find the diagram at your vette photos. Nice job witht he A/C though!

The fuses all check out ok. Parking lights are out in the front and rear of car. I thought this weird as they *should be* seperate wire harnesses. The dash lights as well as console lights are out. I need to know where the grounds come together. Anyone?

 

On an old car, the fuses can LOOK fine and still not work. This has happened to me several times over the last 30 years I have owned my '69 (It wasn't a creampuff when I bought it and had occational electrical gremlins until I worked them out over the first 15 years of ownership!).

You can check by taking a test light or other jumper and run it from one side of the fuse holder to the other with the lights on. If a test light lights, your fuse is bad and if you see sparks you also have issues. I have found that the fuse holders can be cleaned of corrosion using a .22 caliber gun cleaning wire brush bent at a 90 degree angle.

 

I had a similar problem on my 78 turned out to be the light switch. Over the years it had been getting wet do to windshield leaks. I replaced the switch and all was well.

 

I checked each fuse end to ground using a mutimeter. Fuses check ok.

I put meter in series with pos cable and pos terminal of battery. Read 12.4V. Proceeded to pull each fuse until 12v reading went away. It still read 12.4v with all fuses out! There's a short, right? But where? Why is the front parking lights out WITH the rear parking lights? Shouldn't it be 2 seperate harnesses? I've been trying to work with the wiring diagrams from assembly manual but it's tough going.

 

I replaced switch already having a different/related problem?
I think both switches are good. I double checked the ground strap was connected at light switch.

 

Ken, and it bounced, something about "over quota"....

I'll try again tomorrow.

jcj

 

Sounds just like a problem my son had with his 78 El Camino. I hate to say this but we found the fuse block shorting out and had to rewire the entire car last week! The shorts were in the bulkhead connection to the fuse block and we were losing circuit after circuit. Fuses were OK but there was no power at some points.

 

I finally installed new headlight switch that was working fine and now this has happened.

As much of a beech it is, retrace your steps to when the lights wereworking properly. What that might entail is replacing the new switch with the old again and check the lights.

 

I found that this "short" has been giving trouble for some time as the main plug "connector" with wire Brown #20 has been taken out of the plug and reconnected to the wire harness thereby bypassing the conector plug. This tells me that this circuit has given trouble in the past. Maybe they suspected it wasn't making a connection in the plug and bypassed it. When problem "disappeared" they thought they fixed it. Right now it's all working BUT I didn't correct anything. It's a pinched wire or chafed wire or a poor ground. If I knew exactly where each harness or cluster ground is located, I'd go through each one. This is something a wiring diagram can't do. Experience thru years of working on C3's could help here. Thanks to all who have replied o far. I appreciate the help and support. I will post when and IF I find it.

 

Sorry about that. I realized this morning the mailbox was full. I hate that!

 

I've got that exact problem, but I do not have all wires hooked up yet. I installed a new radio and it works. Used the yellow wire for bat, black wire for ground and the last wire is gray which is not hooked up. Everyone keeps saying it's for my dash lights but where? Yes I replaced the light switch to I have posted many questions and even ordered a diagram from Don, but it was no help.

 

The wiring diagram shows all gray wires as console cluster lamps and instrument panel lamps. That gray should attach to the base of a lamp socket somewhere. It could be the radio, heater lamp, console lamp.These are the lamps/bulbs that light up the instruments.
My problem "disappeared". I have to believe my gremlins are dirty contacts at the fuse panel. Good luck with your problem. If you can't fix it, hopefully it will disappear.

 

I have to tell that all those lamps are all accounted for, it's the gray wire with the radio wires. IS that supposed to have a lamp socket is that what your telling me?

 

I had a similar electrical short which I tracked down today (I think!)

No dash lights
Tail lamp fuse blows.
Extra Note: The fuse blows when I go to the full CCW position.



2 Little plastic bits (1) broke off cylinder (2) allowing shaft (7) to come in contact with dimmer wiper (3).

The dimmer wiper (3) picks up 12 volts off the spring (5) and outputs it on the center contact (4).
When you turn full CCW, the wiper (3) contacts the 12V post (11).
Therefore, the full 12V is on the wiper which is shorted to the shaft (7).

Internally, the shaft snaps into the contact carrier in hole (8).
On top of the contact carrier, is the position clicker.
The bump rides in the depressions on the housing (10).

When the **** is turned full CCW, the bump on (2) pushes the switch contact arm (6) up against the housing (10).
The switch contact arm (6) is the ground return for instrument panel.

Remember how the housing (10) was live because the little plastic bits broke off and the shaft has 12V on it?
Well as soon as you turn it full CCW, 12V meets ground and the fuse blows.

New switch on order.
Will update if anyones interested.

 

Nice post kilroy