#11 Fuse on '71 1.7?, It's listed as Int. light, warning light, buzzer ... it fails when Options

[Eddie914]

My '71 3.2 (converted from a 1.7) has lost it's fog lights (It's ONLY headlights since the original pop up headlights have been removed).

I am working on tracing the short but noticed that the #11 fuse (second from the right - near the center of the car) fails when the foglights are switched on. All the documentation I review indicates that #11 should be for Interior lights, warning light and buzzer (none of which remain in my car) and #10 should be fog lamps.

Can anyone shine a little light on this subject for me.

The foglights have been working great for the last few years until a lapping day last month where it rained ALL day.

Thanks

Eddie

[swl]

I pulled out the magnifying glass and had a look at the 71 usa wiring diagram. Wanted to see if the fog lamp relay(53) was somehow associated with fuse 11. Couldn't really see anything though I confess that I can't really figure out that combo relay(27). Nothing jumps out at me so Slits may have the right idea that something has been screwed up along the way.

Maybe another way of troubleshooting might be remove the fog light relay and poke it with a voltmeter. Pin 30 should show 12V. This is the power that gets switched to the fog lights. It comes directly from fuse 10 if the fuse box is still wired correctly. It should be there even with the key off.

If you get 12 V on pin 30 then look at pin 85. That is the pin that will fire the solenoid of the relay. It looks like your lights need to be on for that to happen. I think that is where the combo relay comes in - provides power to the solenoid if the headlights are on.