My 67 442 has suddenly lost all or most of its electrical power. Was working fine when I parked it last, then about a week later, nothing. The battery is fine and fully charged. I have power coming out of the horn relay and junction block. The horn will sound. No ignition, no headlights, interior lights etc. Fuses all appear ok. WHere should I look next?

 

I'd start with the body ground from the engine block to the firewall.

 

Check your ground wire(s). I'm not 100% certain of location(s) on a 1967, but you should see a large ground wire from the battery (-) negative terminal to the engine block. Remove the attachment point end of that ground wire, clean both the block area and the negative terminal well with a wire brush, etc., look for corrosion - it may have even come loose - then reattach. You might have a smaller ground wire from the battery (-) negative terminal to the chassis - often near the fan shroud, same thing - remove, examine, clean reattach. Check for a ground strap/wire from the rear of the engine which leads/mounts to the firewall - same routine.

 

If the horn works, the body ground is probably fine.
I'd start at the ignition switch. I got a replacement pigtail from https://jcaparts.com/

 

Follow the main feed wire from the horn relay through the bulkhead connector to under the dash.

 

The horn can ground though the column as long as the ground strap at the rag joint is good

 

I appreciate the reply from all. The grounds do appear to be ok as does the main going to the fuse panel. I was suspect of the ignition switch but wasn't ready to jump in on it with out some consultation. I will start there next and see if that resolves the issue. Thanks

 

We're all just guessing. Buy a test light or voltmeter and trace the wiring to find the problem. Shotgunning this is a really bad way to troubleshoot.

 

Agreed, but it's still better than parts changing......lol. (FWIW I can't even find what "shotgunning" means but when I googled it I got some pretty strange results )

I've never seen an ignition switch just stop working. Usually when you jiggle them a little they work....for a while. There are a lot of things that can cause what you're describing. If you have the mechanical ability, the first thing I'd do is get a good 68 wiring diagram (I can email you one if you send me your email address). Probably half the time I've seen the whole dash die, it's the chassis ground. If you don't have tail lights, that's a good indication the chassis ground is bad too.

Good luck,

 

Mike - We have a 1968 wiring diagram but the OP has a 1967 - are they the same?

1968 A body wiring diagram

 

Sorry, my bad. I'm sure they aren't but they would be similar (that is my scan though, my grubby fingerprint is in the upper right......lol)

 

 

The ignition switch has nothing to do with the headlight operation. As stated above, do some troubleshooting and see where the power drops off the main feed. You can use the 68 wiring diagram as a general reference, just note there is no fusible link feeding the cabin power on a 67.

 

shotgunning, also known as firing the parts cannon.

 

You are correct. Troubleshooting auto electrical is next to impossible when you don't have all the information, background, poster's technical abilities, or much of anything else. I'm a bit of a sociopath, so i occasionally throw things out there for personal amusement. Carry on.
I did, in fact, have a loose socket on my ignition switch which caused intermittent wiper and turn signals and did get the pigtail from Jurassic.