My coolant low level light came on I checked the antifreeze and it was normal can this be a failure of the coolant sensor ?
It could be the sensor, I replaced mine when I seviced my C230's coolant system.
the translucent reservoir was at "full hot"? and you weren't overheating...yes would suspect the sensor...but first NEW battery is required on acct of the age of this vehicle and please clean the 1/0 battery cable as it attaches to the frame/fender/ground...this is an important one for normal operation of the ECU~
Here's a link to your part, OEM is $20 + shipping. http://www.partsgeek.com/catalog/2002/bmw/330ci/cooling_system/coolant_level_sensor.html
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