What module makes the 'decision' to turn the fans on???

So let me answer the question for my car. That may trigger an answer for his car.

The Climate Control Module, N22 does that. It's the main push-button panel located on the dash. The B10/8 sensor feeds this module and when the resistance gets to about 315 ohms, the signal is given to turn the fans on.

So what's the equivalent for his car???? Same module in the dash???

Corey, it could be that the wire harness is broken at or near the end of the plug that mates with the CT sensor. That would explain you problem nicely since an open circuit appears as high resistance. If you see that it's 'brittle', it's very likely to be open.

Could also be a bad sensor: measure the resistance of it when the car is warm. Remove the plug and measure with an ohmeter: sb about 320 ohms or so at about 95C. If way off, then something is wrong with the sensor.

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Regards . . . . JimF
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'94 S500 Cpe

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