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Camshaft Position Sensor: Description and Operation

PURPOSE
The camshaft position (CMP) sensor is a hall-effect type sensor used to detect the camshaft's position.

OPERATION
The sensor is provided with 12 volts from the fused ignition switch output circuit and the powertrain control module supplies a sensor ground. The CMP sensor has a 5 volt pull-up from the PCM. The sensor signal is created when the distributor's pulse ring is rotated past the camshaft position sensor.

NAME OF CODE:
No Cam Signal at PCM

WHEN MONITORED:
The crankshaft position sensor signal trouble code is not set. With the ignition in either the start or run position and battery voltage between 4 and 15 volts.

SET CONDITION:
Too many crankshaft position sensor signals detected without any camshaft position sensor signal

POSSIBLE CAUSES:
- Open fused ignition switch output circuit (12V)
- Open sensor ground
- Damaged pulse ring
- Failed sensor
- Failed PCM
- Inoperative distributor drive
- Broken timing belt
- Connector terminals
- Connector wires