Several times in the last few weeks whilst driving my 1994 940GL wagon with the rear window heater on, the warning light on the dashpanel with the lightbulb emblem comes on. Sometimes it goes off again by itself. One thing I have noticed though, is that if I turn off the rear window heater, the warning light goes off straight away. I've done this the last 2 or 3 times and it worked every time.

The warning light never comes on straight away - it comes on after the rear window heater has been on for approx 10 minutes or so. I kind of like it as it often reminds me to turn the window heater off, as after 10 minutes it has usually done it's job anyway. However, I'm sure that this isn't the intended function of this warning light !

Anyone had a similar fault and can suggest where to start looking ? Dodgy earth somewhere ??

Got my redundancy letter today (another casualty of the Tyco conglomerate global restructuring), so from Oct 31st I may have a lot of time to potter around on the car...

John Marshall
1994 940GL 161,000km
Christchurch NZ

Sorry about the global event. Been there once recouped and dodged it many, many, times. Talk about globalization, I am in the US, my manager is in India, and his manager is in Belgium. I am in an almost safe zone now since I have <6 months until I'm “eligible” with age and time.

You may be on to it. According to the 1995 wiring diagram, the rear defroster, license plate, lights and the LH tail light share a ground at the LH tail light via a branching point somewhere, on, on, on, a wagon only.

Good luck
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Tom F. Three 940s. '93 T-Rex now running. Mods, RainX. Lien holder on two more (the kid's). Rust In Pieces, '78 245