Electrical gremlin
In this map, you can see that the headlight switch gets it's power directly from the #1 splice, on the alternator side of the ammeter but before the ignition switch. That means that you can use the headlight switch as a diagnostic tool.
Like this;
If when your system crashes, the headlights still work, then the problem lies AFTER the #1 splice, towards the ignition sw.
But if the headlights quit too, then you gotta work backwards to the battery. And as you can see, there are only three items in the path; the ammeter, the bulkhead, and the F-link. Well, 4 if you include the binding post on the starter-relay.
The bulkhead connector is a known trouble-spot.
On my car I just punched a hole thru the connector and cut the metal bits off; then soldered a heavy gauge insulated wire across the ends. That was like two decades ago, and never had a problem since.
Yes you can replace the the F-link with a big fuse; but that defeats the purpose of the F-link which is to endure short-term overloads. The fuse will just blow; and you better have a handful of them in the car at all times for diagnostic purposes.
As for the ammeter; notice the studs have a nut on either side if the connecting wires. Be sure you don't overtighten the outside nut without anchoring the inside nut, cuz if the post twists, you can bet the ammeter is close to being junk. Also; check out what is behind the cluster face, where the ammeter resides. In My car, the pedal bracketry is right there, and if I'm not careful, the always-hot ammeter wires can easily contact that metalchit with predictable results; always disconnect the battery when fiddling with the ammeter.
In this map, you can see that the headlight switch gets it's power directly from the #1 splice, on the alternator side of the ammeter but before the ignition switch. That means that you can use the headlight switch as a diagnostic tool.
Like this;
If when your system crashes, the headlights still work, then the problem lies AFTER the #1 splice, towards the ignition sw.
But if the headlights quit too, then you gotta work backwards to the battery. And as you can see, there are only three items in the path; the ammeter, the bulkhead, and the F-link. Well, 4 if you include the binding post on the starter-relay.
The bulkhead connector is a known trouble-spot.
On my car I just punched a hole thru the connector and cut the metal bits off; then soldered a heavy gauge insulated wire across the ends. That was like two decades ago, and never had a problem since.
Yes you can replace the the F-link with a big fuse; but that defeats the purpose of the F-link which is to endure short-term overloads. The fuse will just blow; and you better have a handful of them in the car at all times for diagnostic purposes.
As for the ammeter; notice the studs have a nut on either side if the connecting wires. Be sure you don't overtighten the outside nut without anchoring the inside nut, cuz if the post twists, you can bet the ammeter is close to being junk. Also; check out what is behind the cluster face, where the ammeter resides. In My car, the pedal bracketry is right there, and if I'm not careful, the always-hot ammeter wires can easily contact that metalchit with predictable results; always disconnect the battery when fiddling with the ammeter.