GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P000A: Intake Camshaft Position (CMP) System Slow Response

DTC P000B: Exhaust Camshaft Position (CMP) System Slow Response

DTC P0011: Intake Camshaft Position (CMP) System Performance

DTC P0014: Exhaust Camshaft Position (CMP) System Performance

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Intake CMP Actuator Solenoid Control

P2088

P0010

P2089

P000A

Intake CMP Actuator Supply Voltage

--

P0010

--

--

Exhaust CMP Actuator Solenoid Control

P2090

P0013

P2091

P000B, P0014

Exhaust CMP Actuator Supply Voltage

--

P0013

--

--

Circuit/System Description

The camshaft position (CMP) actuator is attached to each camshaft and is hydraulically operated in order to change the angle of the camshaft relative to crankshaft position (CKP). The CMP actuator solenoid is controlled by the control module. The control module sends a pulse width modulated signal to a CMP actuator solenoid. The solenoid controls the amount of engine oil flow to a CMP actuator. The CMP actuator can change the camshaft angle a maximum of 20 degrees. The control module increases the pulse width to accomplish the desired camshaft operation.

Conditions for Running the DTC

    • The engine speed is between 736-6,016 RPM.
    • The engine oil temperature is between -10 and +130°C (+14 and +266°F).
    • The commanded camshaft position is stable.
    • The battery voltage is between 10-16 volts.
    • DTCs P000A, P000B, P0010, P0013, P0014, P0016, P0017, P0335, P0336, P0340, P0341, P0365, P0366, P2088, P2089, P2090, P2091 are not set.

Conditions for Setting the DTC

The actual camshaft position does not match the commanded position.

Action Taken When the DTC Sets

DTCs P000A, P000B, P0011 and P0014 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P000A, P000B, P0011 and P0014 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

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

  1. Observe the engine oil level. The engine oil level should be within the operating range. Refer to Approximate Fluid Capacities.
  2. Ensure the vehicle has the correct engine oil and is not old, burnt, or contains additives. Refer to Checking Things Under the Hood in Service and Appearance Care within the Owner's Manual.
  3. If the vehicle has the incorrect engine oil, is old, burnt, or contains additives then change the oil and filter.
  4. Test the engine oil pressure for correct operation. Refer to Oil Pressure Diagnosis and Testing.
  5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

Important: You must complete the Circuit/System Verification before proceeding with Circuit/System Testing.

  1. Test for less than 1 ohm on the applicable CMP actuator solenoid ignition voltage circuit.
  2. If greater than 1 ohm, test the ignition voltage for an open/high resistance. If the circuit tests normal, replace the applicable CMP actuator solenoid.
  3. Test for less than 1 ohm on the applicable CMP actuator solenoid control circuit.
  4. If greater than 1 ohm, test the control circuit for an open/high resistance. If the circuit tests normal, replace the applicable CMP actuator solenoid.
  5. Inspect the affected CMP actuator. Refer to Camshaft Cleaning and Inspection.
  6. Inspect the engine timing components. Refer to Timing Belt Replacement.

Component Testing

  1. Measure the resistance of each CMP actuator solenoid valve assembly. Resistance should be between 8-12 ohms.
  2. Connect a jumper wire between the CMP actuator low reference circuit at the solenoid and a good ground. Connect a fused jumper wire to the CMP actuator high control circuit at the solenoid. Momentarily touch the fused jumper to B+. Observe the spool valve inside the CMP actuator. The spool valve should move from fully closed to fully opened position.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Camshaft Position Actuator Solenoid Valve Replacement
    •  Control Module References for replacement, setup, and programming