1967 Electrical issues. Need help!

[Keith B.]

I am completing the restoration of a 1967 big block. I have gone through my wiring harnesses and have had success with all of the rear lights, including the brake and tail lights, license, lamp light, rear compartment, and reverse lights.

On the interior of the car I have dash lights, clock function and light, lighter, blower motor, glove box light, parking brake lamp, bright lights lamp signal (red), flashers work in rear

1. I do not have the lights when the doors open down by the fresh air vents, but rear compartment light comes on

The car turns over. I have not started it yet.

2. No horns but can hear a click at the horn relay

3. Only the bright lights come on the right side with no lights anywhere on low beam. I have put two different dimmer switches in with the same results.

4. No parking lamps. Lamps do not flash when hazards are on and do not blink or light when turn signal is on.

I have replaced the turn signal switch

My head light buckets function well. Was getting flashing of headlights (red) when I had brights on and buckets down on the dash.

Need help with listed items above. I think I am missing something such as a ground. I do have a ground connected to the core support. I am restoring the car and have painted the core support. I did not remove paint when I connected the ground. Because I have power to the headlight motors I assumed the ground was functioning correctly. Again, I have power to headlight motors and lights on one side. I know there are separate grounds on the headlight motors. I am not sure if the ground at the core support comes into play with the headlight motors?

Thanks for any advice. I do have a 12 volt tester and can check for things if someone has a solution.

[Tim L.]

Keith, I'm also completing the restoration on my '66 L79 and feel your pain! I've been chasing electrical gremlins for over two weeks. All new harness, rebuilt or new componets and many of the same issues. I have traced a few down to bad grounds (paint under). Using the wiring diagram trace wires and check continuity, also use a test light. I'm still chasing!
I've taken a break from electrical - Upholstering my seats!

Good luck
Tim

[Mark F.]

Keith,

This is probably remedial for you, but a lot of ground connections (particularly those that need to connect to painted parts) use star washers with teeth-like edges that "dig into" the part that has continuity back to the negative battery terminal.

Example: for the engine mount ground strap, the typical sequence (and best for electrical grounding) is: frame; star washer; ground strap; and screw (bolt).

maybe check that the star washers are there ? - and if so, maybe crank the bolt/screw 1/4 turn to ensure it's biting thru the paint ?

[Duane G.]

keith, are you using a wiring diagram? although these cars are simple compared to today, they are still difficult if things don't work, and that diagram shows electrically how things work, but not the actual position of items such as where the ground wires are screwed down to ground metal (I.E. frame ground point, etc). I have a 67 BB which I restored 28 years ago. and that diagram got all my stuff working. First, at each device that does not function, you need to use the tester to determine if the device is getting positive voltage. Connect the tester common wire to the battery negative or to a known good ground source such as a clean bolt on the engine and then touch the testers other wire to a known good positive location such as the battery positive, then you know the tester is working with a good ground common point. don't move the ground common point wire of the tester, but now you can go looking with the other tester wire for where the positive is suppose to be. For example, on the door courtesy lamps, they use and orange positive wire and white for the ground. When a door opens the door switch pops out and completes the ground path for the courtesy lights. The lights have constant 12 V+ all the time, but wait for the ground to connect thru the door switches or the head light switch when turned to courtesy light "on" position. you will likely have to use some extra test wire for the ground common point to connect to the tester, as you move around the car, because once you have a known good tester ground point, you want to keep it. You can use this method in a similar fashion to find if the grounds are the problem on a particular device by keeping the good known ground reference on the meter common wire and now switch the tester to resistance scale: use the other tester wire to search if the ground wire is on a particular device is good. verify meter reads near zero ohms, thus verifying the device wire is connector to a good ground point. If you have a resistance reading other than near zero ohms (or the meter shows infinite ''wide open'' resistance) it means a bad or no ground on that devices wire. Be careful when using ohms scale as if you accidentally touch a point that has positive voltage, you could damage you meter. When looking of grounds , I have, at times, first set the tester on volts scale, then touch the wire I think is ground and if the meter shows no voltage on that wire then switch to ohms scale and look for resistance.