I am trying to find the ambient temperature sensor on my '94 940 wagon. A manual I have says it is located behind the bumper, but I could not find it there. Does anyone know exactly where the sensor is located. My gauge is reading -188 degrees and the red freeze light is on. I am hoping it is a bad sensor or its wiring connector that is causing the problem. Thanks in advance for any assistance! John

As you are looking at the front of the car, the sensor is located below the bumper on the right-side of the lower grill. When you do find it you may want to check the connections behind the sensor. I have a '93 940 sedan with the ambient sensor, but mine displays 'C instead of 'F. Hope it works out for you.

Ah, jeez, another Canadian in denial. What did you expect Edmonton to be like, anyway? Just put on another plaid jacket and bear it.
Really, the sensor is down under the driver headlight. Chris is right: wiring is the problem, or a corroded ground. Now is the time to clean, de-oxidize and protect your ground planes.

Generally it's a fault in the wiring or the ground that drives the gauge to be that cold.

Either that, or it's -188 degrees out. Good luck getting the car started.

The ambient temp gauges are more accurate than that, usually. If the thermocouple is corroded at the ground, or fouled with slush and debris, it can cause the same effects.

But the bad ground is VERY often the case.
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chris herbst, five volvos.