1967 Electrical Issues

[Keith B.]

I have a few separate issues that are causing me problems.

I am doing a full restoration on a 1967 big block and prior to taking the car apart I made sure that everything was working correctly. This is a former Duntov car and has been through many many operations checks.


1. The low beam headlights will not come on. I have tried two different highbeam switches and I get the same affect. I do have both sides high beams functioning correctly, but I do not have low beam lights at all. The light switch pull works. The parking lights come on at the first notch, but when I pull the switch to the next level the parking lamps extinguish as they should and the headlights simply don’t come on. If I hit the highbeam switch the highbeams come on but no low beams.


2. The right blinker is not functioning. Left works fine. However, I do have hazard flashers and I do you have brake lights. I did change the turn signal switch prior to restoring the car. It was functioning properly when I took the steering column out. When the headlights are on the on position and I put my foot on the break the inside right light tail light goes out. The right inner also seems like it is dull compared to the other right light. I did change the bulb and got the same reactions.

3. I have power to the radio but when I turn it on I get nothing. I also can’t get the light to work on the radio.

You are all much smarter on this than I am. Any help will be appreciated. All the wiring harnesses are original.

[Tom K.]

Re: 1967 Electrical Issues

Keith, It sounds to me like you have several grounding issues. I haven't gotten this far on my 67 yet but from what I have seen here and my somewhat limited electrical knowledge that usually seems to be the main problem. I would start with checking all of the grounds at the lights to see if that helps. A volt/ohm meter would be a big help in verifying connections at the lights and at the radio. Hope this helps. I'm sure others with more knowledge will also reply.
Tom

[Ray G.]

Re: 1967 Electrical Issues

Hello;

Check the firewall connectors for wire ends staying in place.

Check for proper grounds.

Is the foot pedal low/high beam switch sticking ?

The radio off/on switch/potentiometer inside the radio has many functions, it may need to be cleaned & serviced

my .02
Ray

[Leif A.]

Re: 1967 Electrical Issues

Doing a restoration on a 52 year old car and not changing the wiring harness(s) is just asking for the types of problems you're currently experiencing. Everything may have worked prior to disassembly, but that original harness is quite brittle...they were never designed to last 50 years...more like 10. With all the movement of the original harness during restoration who knows what has happened internally to those wires. You may be able to resolve all your issues without changing your harness(s) but going forward you're looking at more and more electrical gremlins. Simply MHO.

[Richard G.]

Re: 1967 Electrical Issues

First things first:
Have you checked the bulbs?
Both could be out?
Rick

[Gerard F.]

Re: 1967 Electrical Issues

2. The right blinker is not functioning. Left works fine. However, I do have hazard flashers and I do you have brake lights. I did change the turn signal switch prior to restoring the car. It was functioning properly when I took the steering column out. When the headlights are on the on position and I put my foot on the break the inside right light tail light goes out. The right inner also seems like it is dull compared to the other right light. I did change the bulb and got the same reactions.

Keith,

Not too sure about your items 1&3 which seem to be related to the light switch and lighting circuit, but item 2 seems to be related to the signal switch. The headlight system is on a different circuit and uses a different element of the signal light bulbs.

If all your signal bulbs light and blink as they should when the hazard switch is pulled, then the wiring and bulbs to the signal element is OK. The brakes, hazard and signal switch use the same element of the dual element bulbs, and go through the signal switch and are on three separate circuits.

Attach is a schematic of the 67 (&68) signal switch:



If signal lights work on one side only or the problem is only with one signal light, the problem is probably in the signal switch and particularly the cam and cam contacts within the switch. I have been through 4 switches on my 67, and on one of the new overseas switches(which lasted only 6 months), I found that they had put too much grease on the cam. This created too much resistance and heat (melting the cam) and bunged up the cam contact.

You can test the signal switch without taking apart the column. Just disconnect the switch from the harness, and use an ohm meter on the switch side for the various circuits from the diagram. Use the positions of wiring harness of the schematic to identify the circuits. If you get very high resistance or an open circuit which should be closed for the operation, you will have found the culprit.

Hope this helps,

[Stephen L.]

Re: 1967 Electrical Issues

Jerry, Nice job on the schematic. I copied and placed it in my electrical records for my 67.
Thanks
Steve

[Edward D.]

Re: 1967 Electrical Issues

Agree with poster advising you to check grounds. On taillights each light housing has a black ground wire attaching to one of the mounting lugs, if loose or corroded these can cause problems. On headlights, check for 12 volts at the low beam bulb plug when the headlight switch is on, ground your voltage tester to a known good ground when doing this. If no voltage, trace back through the wiring to find the power interruption issue. If 12 volts present, then check the ground lead on the plug for continuity to ground. If no continuity, find the ground fault, typically it is where the lights ground lug to the radiator support. Get a wiring diagram, the large version is easiest to read.

[Daniel Y.]

Re: 1967 Electrical Issues

Keith, encountered similar issue and found that the headlights were weak. after replacing the bulbs - everything worked correctly. I would not have believed it but Elio Martin turned me on to the possibility

good luck!
I

[Tim G.]

Re: 1967 Electrical Issues

Hope to see the car done, I bet it looks great.