Defroster/turn signal causing headlights to turn off?

[daveola]

Starting today the gremlins have taken control of my dash.

Everything was working fine yesterday, but now:

• If I put the defroster on low, the defroster doesn't come on, and sometimes the headlights turn off.
• If I put the defroster on high, the defroster may or may not come on - but if it does, then the headlights definitely turn off.
• If I use the right turn signal, everything works fine.
• If I use the left turn signal, then either the headlights blink on and off while the turn signal blinks off and on, or else the headlights stay on and the turn signal flashes quickly.

I've also noticed that sometimes if I try to run the defroster, the left turn signal indicator light on the dash will glow slightly.

What could have caused all of these systems to suddenly get intertwined like this??  Any thoughts?

[luvrbus]

The ground wire now to find the sucker

[brmax]

Wow! Dave I would check all signals for proper / not dimming, in check mode. Particularly left but then they are 24v right? and sometimes its sneaking to use headlight system of 12v circuit? when defrost system use. Is your bus a 9 or 102,  not sure if I could use an older 9 schematic to help much.
Floyd

[daveola]

I always forget to post this right away:

MCI 102A3

[daveola]

And everything should be 24V except for the two headlights, right?

Either way, it's both headlights that are switching off with the turn signal.