I'm assuming you leave the switch in the headlight position?

Just turning the key off should drop the headlight relay and kill all lights.

Do the headlights go off when key is turned off?

You say "tail lights" stay on. Front parking lights too? (same circuit)

Do the tail lights go out if you turn the light switch off?

Probably a corroded/shorted Headlight relay, down under the hump on left side of driver's floorboard on '86. Look for harness with a Red/Green wire leading down to the relay -- which will also have 2 yellow wires and a white.

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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

I hate to ask the obvious, but it's not just that the switch is in the middle (park lights only) position is it? It's supposed to do that. I figure you know that but thought I'd ask.

Anyway I'd look for possible damage to the wiring harness around the headlight high/low relay. Maybe something from the battery hot terminal rail has rubbed against a wire feeding the headlight circuit. I had a problem related to this in my 87, when the coil/ ps reservoir mounting bracket fatigued and broke off, cutting against a few wires. I didn't get a short but I can sure see how that could happen.

Good luck!
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Rob Bareiss, New London CT ::: Roterande Fläkt Och Drivremmar!