temp sensor, how to test?

[z3ds]

My temp gauge stopped working. I shorted the wire that connects to the sensor to the ground the gauge didn't moved. I connected the sensor to a volt meter, it put out random resistance value. well i didn't really know what to look for with the vometer.

how do i test the sensor correctly?
I also searched the part # of the brown coolant sensor but was unsuccessful does anybody know and where to get one? thanks

[z3ds]

ok i found the part didn't found it at first coz i was searching only on the 24v forum http://www.pelicanparts.com/bmw/cata...WATmis_pg4.htm