Very simple car with a 318 and very few accessories. Have owned this car for years, and this problem has surfaced a couple of times recently. Absolutely no electrical working from inside the car. Not even the horn, headlights, or dome light.

Battery is good/charged and good voltage up to bulkhead. I removed the bulkhead connectors and fuse block and inspected and cleaned all male and female connectors,etc. there. No corrosion or apparent bad wiring. If I jump/arc the starter relay, I get full strong power to the starter just fine, so no terminal or fuseable link issues under the hood.

Each time this has occurred, it starts at night when everything starts to dim, with ultimately full loss of electrical. I hit the horn and it fades out to nothing. Then no start, no lights, no guages...nothing. The previous time it happened, I took it to a local shop and they spent time testing and looking at the connections like I have, mostly at bulkhead and under/behind the dash. They said when they reconnected the bulkhead, things started working again. I'm not sure how confident I am in that, but that's what they said. That lasted a couple of months. This time, same symptoms and failure, and I've cleaned and thoroughly inspected the connections multiple times. I even took out the fuses and cleaned those contacts. Still no electrical at this point!

The condition of wiring doesn't look bad at all in terms of shielding, corrosion, connectors, etc. What else could it be? We questioned the ignition switch, but I don't think it could prevent things like the horn or dome light from working. Any input would be greatly appreciated!

 

What you don't say is that you have checked out all the grounds, engine, body ect...
A bad ground can give false symptoms to electrical problems. Go over all of them...

 

Negative terminal to body and engine, and engine to body, are intact. Where else should I look?

Thanks

 

Hummmmm.... I'm going to guess that the problem is the Amp Gauge or the Voltage regulator.. Just a hunch. It loosing something in the red or Black wire for sure.

 

Well, you may be on to something re amp gauge. Poked around up the without being able to see much, and things started working again! Something must be loose or rough connection...very difficult to get access.

 

Yep... Got to pull the cluster out, and also try not to break anything else.... Take your time...

 

 

I had a similar problem on my 68 fury ended up being a fusible link on the outside of bulk connector