Pin 1 is +5V, pin 2 is Ground and pin 3 is the signal. Use analog voltimeter in pin 2 and 3. Crank the engine: the pointer of the voltimeter shoud oscilate in range 0V to 5V.
Also you can use diagnostic scan tool capable of testing sensors. This is the easiest way.
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Thursday, April 30th, 2009 AT 3:01 PM