CRANKSHAFT POSITION SENSOR Jeep Commander I

CRANKSHAFT POSITION SENSOR

The crankshaft position sensor is located at the left rear of the engine just above the starter motor. The sensor detects the crankshaft position contactlessly (hall effect) by means of missing segments on the tone wheel behind flex plate. The electronic control module (ECM) detects TDC position of cylinder 1 by means of the signal supplied by the sensor. Injection timing is synchronized by means of the camshaft signal and the crankshaft signal. This sensor is used to detect engine speed.

The crankshaft position and engine speed are detected contactless signal (hall effect). The distance between the crankshaft position sensor and the gaps of the tone wheel is fixed by the installation position.

When the crankshaft rotates, an alternating voltage is generated in the crankshaft position sensor by the gaps of the tone wheel located behind the flex plate.

In this case, the metal portion of the tone wheel generates a positive voltage pulse and the gap in the tone wheel a negative voltage pulse. The distance from the positive to the negative voltage peak equals the length of the gap.

The gap created by 3 missing teeth has the effect that no voltage is generated in the crankshaft position sensor. This gap, or time without a signal from the crankshaft sensor, is analyzed by the ECM in order to detect the TDC position of cylinder 1

Scheme 92

1. Disconnect the negative battery cable.
2. Raise and support the vehicle.
3. Remove the crankshaft position sensor heat shield (1). (Scheme 92)
4. Disconnect the crankshaft sensor wiring harness connector.
5. Remove the bolt and sensor (2).

1. Clean the crankshaft sensor bore and install the sensor (2). see scheme 167 Tighten the bolt to 9 N.m (80 in. lbs.).
2. Connect the engine harness connector.
3. Install the heat shield (1). see scheme 167
4. Lower the vehicle.
5. Connect the negative battery cable.