hi, im trying to test the crank sensor in my 96 4.0, there are 2 wires running into the plug. one wire has 2v on it, and the other has nothing. thats with ignition switch on 2 and start. i put 12v to the wire that had 2v and still no spark. are both wires power and makes contact as it runs through the sensor or is one of the wires ground. because the one wire when hooked to 12v it gets hot which means the wire is grounded out somewhere, unless its supposed to be a ground. i read on another site that its a alternating current making contact as it runs through sensor but im not sure. any help please

 

The ECU sends a voltage through one wire. When the sensor meets the mark on the timing gear, it closes, and sends a + voltage through the other wire. The pulsating/ alternating signal is what the ECU reads to determine timing and engine speed.

Read the voltage at the wire with none and crank your engine. If the output pulses, your sensor is fine. I don't think it reads in 12V.

 

Down load a free copy of a Rave CD and it should give you everything you need to know.