Gauge lights

[Chevystep]

Finally put a battery in the 66 restoration and cranked it! No fuel though, so a new fuel pump is on order. One thing I noticed, the gauge lights were on the minute I hooked up the battery, is this normal and did I never notice that before the restoration? Shouldn't they only come on through one pull on the switch to parking light position? Do I need to pull the switch and continuity check it from power tap to other positions? Looking at wiring diagrams, the grey wire feeds these bulbs and goes straight to the fuse panel. What am I missing here? They DO dim when the switch is turned....so there must be some switch connection...

[ray_mcavoy]

You're right, the gauge lights should only be on when the headlight switch is pulled out to either the first (parking lights) or second (headlights) position.

Yes, the grey wire that powers these lights leads directly back to the instrument lamp fuse in the fuse panel. The other side of that fuse is fed via a dark green wire that leads back to the headlight switch. The headlight switch is responsible for providing both the dimming and the on/off control of power to the dark green wire so you could be dealing with a defective switch. Also check for any add-ons connected to these wires (such as from an aftermarket stereo) that could potentially be backfeeding power to these circuits.

[damnyankee36]

Just for grins, pull the gauge light 5 amp fuse and the tail light fuse one at a time. Interesting to see what will happen. It might help you start you on the right path.

[Chevystep]

Thanks guys! Gonna pull the switch and check continuity between power and dark green. Don't know if the fuse pulling will help at this point since no exterior lights are hooked up yet! Just trying to see if she'll pump fuel, have fire (and fire up) and check gauge stuff before I start throwing on the fenders and such. Just has the new 283 swapped into it and just inner fenders/rad support at this point so I can still get in and around it for engine work....

Time to go play with the multimeter....and it's a new switch, too! And they're pricey!

[Chevystep]

So I've hooked up some multimeter leads to the red power lead on the switch and tried to get continuity between other contacts on the switch as it is operated. Pull it out one pull and get continuity between red and purple or parking lights...but no other lead gets any continuity to red upon pulling the knob out fully. Switch might be bad, but that doesn't explain why my dash lights are on, something is bleeding through somewhere...ordering a new switch, but I've got some more troubleshooting to do...maybe some bleed thru 12V at the fuse panel per damnyankee. The only thing I've changed on the dash light wiring is adding the tach light to the existing grey bulb wiring...

[damnyankee36]

Here's another thought...

Do the dash lights go out when the switch connector is disconnected?

[Chevystep]

Problem solved, went back to first things first and made sure all the right color wires in the switch plug were in the correct position in the plug. They weren't, the double orange wires had been moved to the wrong slot as per the 66 wiring diagram. Moved them to correct spot plugged back in, bat hooked up, all is well....thanks for making me think!

[damnyankee36]

It's always a simple fix. It's the steps getting to the fix that takes so long!!