Colt L4-1795cc 1.8L SOHC (1994)
Crankshaft Position Sensor: Component Tests and General Diagnostics
Harness Inspection
TROUBLESHOOTING HINTS
Hint 1: If unexpected shocks are felt during driving or the engine stalls suddenly during idling, shake the crankshaft position sensor harness. If this
causes the engine to stall, poor contact of the sensor connector is suspected.
Hint 2: If the crankshaft position sensor outputs a pulse signal when the ignition switch is turned to ON, (without starting the engine), the
crankshaft position sensor or engine control module is probably defective.
Hint 3: If the tachometer reads 0 rpm when the engine that has failed to start is cranked, faulty crankshaft position sensor or broken timing belt is
suspected.
Hint 4: If the tachometer reads 0 rpm when the engine that has failed to start is cranked, the primary current of the ignition coil is not turned on
and off. Therefore, troubles in the ignition circuit and ignition coil or faulty ignition power transistor is suspected.
Hint 5: If the engine can be run at idle even though the crankshaft position sensor reading is out of specification, troubles are often in other than
the crankshaft position sensor.
Examples
a. Faulty engine coolant temperature sensor
b. Faulty idle air control motor
c. Poorly adjusted basic idle speed
Sensor Inspection
VOLTAGE TESTING PROCEDURE:
1. Connect an analog voltmeter between terminal 1 and 3 of the crank angle sensor connector.
Terminal 3: Crankshaft Position signal
Terminal 1: Sensor ground
2. Measure the output voltage of the terminals while cranking the engine.
Standard Approximate Values 1.8 - 2.5v (needle fluctuates)
3. When the voltage is abnormal, check the sensor power and ground circuits.
