Is there another coolant sensor on this car, aside from the one(s) on the thermostat housing? This is what happened:

Last Weekend: While changing air filter, and cleaning sensors and connectors, had the coolant temp sensor unplugged and decided to start the car. Engine was warm/hot. Electric fans came on and engine fired right up (no ASR issues since engine was warm).

This Morning: Engine cold, unplugged coolant sensor and started car. Cranked but did not turn over. Tried twice. Electric Fans did Not come on. Plugged sensor back in, started car, it turned over normally. Unplugged sensor while running. RPMs dropped from about 1100 to 600. Waited about 15 seconds for ASR to appear, which it did.

Drove about 5 blocks to shopping center parking lot. Coolant temp was about 45-50. Shut down car. Disconnected sensor. Cranked and car restarted, but no electric fans. Waited for ASR to clear. Drove 20 miles. Engine hot. Shut down. Disconnected sensor. Restarted – electric fans came on full blast, and car started normally.

My understanding was that with the coolant sensor disconnected, the electric fans should start the engine should not. So is there another sensor I am not aware of? Or is there some dirt/corrosion in the sensor connector affecting sensor/resistance readings when weather is cold or damp?

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2008 E350 4matic / Black/Anthracite

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Gone but not Forgotten:
2001 E430 4matic, 206,xxx miles, Black/Charcoal
1995 E320, 252,xxx miles, Black/Grey
1989 260E, 223,00 miles, Black/Black