bad temp sensor?

Hello,
1999 528i here....
Was cruising down the highway free as a bird last night with the AC pumping.
Next thing you know I hear "BING" and the temp on the dash is reading -40C
and the AC quit working. Thought it might be a blown fuse but it was not.
Ate dinner then got in the car. The temp reading started to climb and when it got to near the real temp I popped on the AC and it was working again until a couple minutes later and "BING!" -40C again.
What do you think the problem is? My friend seems to think it's the inside temp sensor gone bad.
Jeff
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Yes, a bad sensor.
It lives in the air duct that directs air to the left front brake rotor and caliper.
In -40 temps outside, odds are good that yo don't need the AC inside, so it turns off.
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It's an outside temperature sensor, not an inside one. Remember, the temp on the dash that you see is exterior.
It's more likely to be the wiring than the sensor itself, but check both. If the circuit is open, the computer will read it as -40. --scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

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I just had the center bering replaced on the transmission. Do you think they could have knocked something loose?
snipped-for-privacy@panix.com (Scott Dorsey) wrote in wrote in message

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They could have, but odds are against it. The temp sensor lives inside the duct that directs cold air to the left front brake rotor. It's easy to replace. Since the failure is that the sensor is unplugged, you could plug it in before buying a new one.
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I doubt it... but get under there and follow the cable and start tugging on it and see. I don't think it goes anywhere near where the transmission is, but I have knocked some stuff out of position that didn't seem anywhere near where I was working myself. --scott
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