I have a question regarding the proper illumination of the demister switch. With the ignition switch turned on, the light on the switch is off. When I turn the headlights on, the light then illuminates. If I then turn the headlights off, the switch stays illuminated. Is this the correct pattern for this switch?

If this is the correct patten for this switch, how would I know when the demister is on if the switch is always illuminated when the headlights are on? If this is the incorrect illumination sequence for this switch, how do I repair the problem?

Thanks in advance.

AP

I think its the demister relay, as it makes a buzzing sound when the headlights are turned on and the car is off. Where can I find one of these, other than at the Volvo dealer. I've looked at fcp groton and ipd, and neither one of them carry this part.

Thanks in advance.

AP

I bet I've got one from an '86. Let me check.
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'93 244: 'A' cam 4 deg. advanced, 25/22 sways, custom heim endlinks, fully converted to poly bushings, HD springs front, wagon springs rear.

Looking at it now, exact same part. Came from a working (if rusty) car. $10 shipped? Email me:

sean.corron(at)cox.net
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'93 244: 'A' cam 4 deg. advanced, 25/22 sways, custom heim endlinks, fully converted to poly bushings, HD springs front, wagon springs rear.

My '85 did the same thing. The ground strap in the left hinge had rotted away. When the license plate lights had power (when the headlights were on), they would find ground through the defogger circuit. It also caused the third brake light to illuminate when the headlights were on...flashing off when the brake was touched. Both were fixed by putting in a new ground strap.

You can test this by running a temporary ground from the tailgate to the body of the car.

The light in the switch is powered by the same terminal from the relay that powers the rear defroster element. If that light is going on/off independent of the rear defroster, then you either have a bad relay or a bad ground. I'd be tempted to blame a bad ground since the headlamp circuit is independent of the defroster.

Good luck!
-Ryan
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Athens, Ohio
1987 245 DL 314k, Dog-mobile
1990 245 DL 134k M47, E-codes, GT Sway Bars, GT Braces
1991 745 GL 300k, Regina, 23/21mm Turbo Sway Bars

Here's another wrinkle to the story...when I don't have the keys in the car, but turn the headlights on, I hear a strange buzzing sound from under the dashboard (the usual 'lights on' chime works fine). I found the source of the buzzing under the dash, and identified what I think is a relay. Here are the photos I took of it. Any idea what this is?

http://picasaweb.google.com/aaronlpratt/MysteryRelay/photo#5227835736488424994

http://picasaweb.google.com/aaronlpratt/MysteryRelay/photo#5227835742369194482

That is the rear window defroster relay.
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'80 DL 2 door, '89 DL Wagon

No, it should only illuminate when it is pressed and actually heating the back window.

Not a clue what's wrong; hate to say it, but you could have some ignition switch problems. Maybe the demister relay?
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'93 244: 'A' cam 4 deg. advanced, 25/22 sways, custom heim endlinks, fully converted to poly bushings, HD springs front, wagon springs rear.

It's strange that it only illuminates when we turn on the headlights. If I turn the ignition on, but don't turn on the lights, it will light when I depress the button. Hmmmm.