Hopped in the Disco last night and turned the headlight switch but they did not turn on. Fog lights work, and so do high beams. I checked the fuses this morning for the headlights and they are good. Swapped one out just to make sure, and it did nothing. Since neither one will work, and since they both use a separate fuse, it is feeling less like a fuse issue anyway.
Is there a ground that is common to them both? I doubt that both bulbs burned out at the same time. I had used the lights for a long drive back from the bay an hour earlier, then used the lights on the way to the store. In the store for an hour, come out, no lights.
Any ideas welcome. Thanks.

 

Try swapping R-11 with R-12 in the engine fuse block and see if that corrects for a bad relay. If no difference then I would say you have a bad headlight switch.

 

Check for power at the lights themselves, you're probably right that the chances that both bulbs burned out simultaneously are slim (not impossible though) you may have had one low beam burned out and not noticed it (especially if you live in the city) but when the second one burned out and everything went dark it was hard not to notice. I find it's always easier to check the obvious stuff first (and not assume) before tearing stuff apart only to find the bulbs burned out.

 

I don't see any labels in the engine block fuse box, and see nothing in Rave either. Which ones areR11 and R12?

 

Turn the fuse cover lid over and you will see what you need.

 

As an update, I swapped the replays and there was no difference. My deduction is that I have a bad stem switch on the steering column. One of my buddies had the same issue on his jaguar and took it apart and cleaned the contacts with rubbing alcohol and it was fixed. I will try that, first, and then order one if that is unsuccessful.

 

Use electrical contact cleaner for possible better results.

 

Alright, I got the switch out, and the blade contacts look clean. I am trying to figure out how to take the rotating switch apart, to see if that contact is dirty. It looks like there is a very small allen screw in the hole on the back of the rotating switch, but my smallest allen wrench (1.27mm) is too big. Has anyone taken this apart successfully?
The other option is to test the power at the lights themselves, right? I am not sure how to do that without buying new bulbs.
Any help is appreciated. Thanks.

 

in taking apart the whole switch, i see that the stalk is only a mechanical lever to slide the headlight switch in the column part of the switch. I see no way to get in that area to clean, so I reassembled and put it back in.
If anyone can explain how I can test for power at the lights, I would appreciate it. Thanks.

 

Oh man, you are into it.
Taking a switch apart is nasty.
I took the window switch apart once.
Got it back together on a D1.

You may want to just try jumping wires on the plug that goes into the switch to see
if you can get the lights on.

I would think that there would be a relay used for the lights..
I doubt they are putting all that current through the switch..
But, who knows?

Also - a ground wire could be off or chewed through.
A squirrel or rat or mouse can buzz thru a ground wire pretty fast.
Happened to a friend of mine on a Dodge Dakota truck.
Took us weeks to figure that out.
We finally had it down to the exact wire and location from the schematic for the truck.
And, yes, a rodent chewed the wire.