The CMP actuator solenoid enables the powertrain control module (PCM) to change the intake and exhaust camshaft timing while the engine is running. The CMP actuator solenoid contains a spool valve that controls the advance of the camshaft. The CMP actuator solenoid valve is controlled by a pulse width modulated (PWM) signal from the PCM. The CMP sensor monitors the camshaft position or the camshaft angle, and compares that position or phase to the crankshaft position (CKP) sensor signal. The PCM determines whether the camshaft angle is correct by comparing the actual camshaft position to the target camshaft position. By continuously analyzing the input of the CMP sensor and the CKP sensor the PCM can detect a fault in the CMP actuator system.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Camshaft Actuator System Description

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Important: The supply of clean pressurized engine oil to the CMP actuator is essential to correct CMP actuator system operation.

1. Observe the engine oil level. The engine oil level should be within operating range.

Important: All CMP actuator system DTCs must be cleared before the CMP actuator solenoid scan tool output control is enabled.

2. Engine running at normal operating temperature, command the applicable CMP actuator solenoid ON with the scan tool. The engine should run rough or stall.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

1. Ignition OFF, disconnect the harness connector at the camshaft position (CMP) actuator solenoid.
2. Disconnect the PCM harness connector X2 at the PCM.
3. Ignition ON, test for infinite resistance between the CMP low control circuit terminal 2 and ground G104.

⇒	If less than the specified range, repair the short to ground in the CMP low control circuit.

4. Engine running, connect the CMP actuator solenoid to B+ and ground with a pair of 10A fused jumper wires. Verify the engine runs rough or stalls.

⇒

If the engine does not run rough or stall, remove the CMP actuator solenoid and verify the solenoid plunger moves 3 mm (0.125 in) when connected to B+ and ground. If the solenoid plunger moves less than the specified range, test or replace the CMP actuator solenoid. If the solenoid plunger moves greater than the specified range, test the following conditions:

•	A plugged or restricted CMP actuator solenoid oil filter

•	A blockage or restriction in the CMP actuator system oil passages

•	Low oil pressure or oil supply to the CMP actuator assembly or actuator solenoid

•	A damaged or misaligned CMP sensor reluctor

•	A worn timing chain and jumped timing--Refer to Symptoms - Engine Mechanical.

•	The wrong camshaft installed

•	Incorrect operation of the CMP actuator assembly--Refer to Camshaft Position Actuator Locking Pin Adjustment.

⇒	If you find any of the above conditions, repair as necessary.

1. Ignition OFF, disconnect the harness connector at the CMP actuator solenoid.
2. Test for 6.9-7.9 ohms at 20°C (68°F) between the actuator solenoid terminals 1 and 2

⇒	If not within the specified range, replace the CMP actuator solenoid.

3. Test for infinite resistance between each terminal and the solenoid housing.

⇒	If not the specified value, replace the CMP actuator solenoid valve.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.