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 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

P0010

P0010

P0010

P0011

Intake CMP Actuator Low Reference

--

P0010

--

--

Exhaust CMP Actuator Solenoid Control

P0013

P0013

P0013

P0014

Exhaust CMP Actuator Low Reference

--

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 12V 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 25 degrees. The control module increases the pulse width to accomplish the desired camshaft operation.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

    • The control module has enabled the CMP actuator.
    • The difference between the desired CMP actuator angle and the actual CMP actuator angle is more than 6 degrees.
    • The CMP actuator is steady for 3 seconds.
    • The condition is present for 13.5 seconds.

Action Taken When the DTC Sets

DTCs P0011 and P0014 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P0011 and P0014 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Camshaft Actuator System Description

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

  1. Ensure the vehicle has the proper oil viscosity.
  2. Observe the engine oil level. The engine oil level should be within the operating range.
  3. Allow the engine to reach operating temperature.
  4. Increase the engine speed to 1,500 RPM.
  5. Command each CMP actuator to 25 percent. The CMP actuator angle desired parameter should match the CMP actuator actual parameter.
  6. 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

  1. Ignition OFF, disconnect the CMP actuator solenoid harness connector at the CMP actuator solenoid.
  2. Test for less than 5 ohms between the low reference circuit terminal B and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance.
  4. Verify that a test lamp does not illuminate between the low reference circuit terminal B and the control circuit terminal A.
  5. If the test lamp illuminates, test the control circuit for short to voltage. If the circuit tests normal, replace the ECM.
  6. Remove the test lamp.
  7. Command the CMP Actuator Sol. ON with a scan tool. Verify the scan tool CMP Sol Ckt Short Gnd Test status is OK.
  8. If not the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM.
  9. Install a 3A fused jumper wire between the control circuit terminal A and the low reference circuit terminal B. Command the CMP Actuator Sol. ON with a scan tool. Verify the scan tool CMP Sol Ckt Short Gnd Test status is Fault.
  10. If not the specified value, test the control circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
  11. Determine that the vehicle has the correct engine oil. Refer to Service and Appearance Care in the owner's manual.
  12. If the engine oil life system monitor displays the Change Oil Soon message, the engine oil is more than one year old, contains additives, or is not the correct viscosity, change the oil.
  13. Test the engine oil pressure. Refer to.
  14. If the oil pressure is low, correct the low pressure first.
  15. Inspect each CMP actuator solenoid valve assembly for the following:
  16. • Torn screens
    • Debris on the screens
    • Debris clogging the oil ports
    • Missing screens
    • Oil seepage at the solenoid connector pins
  17. Connect a jumper wire between the CMP actuator low reference circuit terminal B at the solenoid and a good ground. Connect a fused jumper wire to the CMP actuator high control circuit terminal A at the solenoid. Momentarily touch the fused jumper to B+. Observe the spool valve inside the CMP actuator. The spool valve should move.
  18. If movement is not observed, replace the CMP actuator solenoid.
  19. Inspect the engine timing components. Refer to.
  20. If all circuits test normal, test or replace the CMP actuator.

Component Testing

  1. Measure the resistance of each CMP actuator solenoid valve assembly. Resistance should be between 8-12Ω.
  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
    •  Camshaft Position Exhaust Actuator Replacement
    •  Camshaft Position Intake Actuator Replacement
    •  Control Module References for replacement, setup, and programming