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 Descriptor

DTC P1011: Intake Camshaft Actuator Park Position Bank 1

DTC P1012: Exhaust Camshaft Actuator Park Position Bank 1

DTC P1013: Intake Camshaft Actuator Park Position Bank 2

DTC P1014: Exhaust Camshaft Actuator Park Position Bank 2

Circuit/System Description

The camshaft position (CMP) actuator system enables the engine control module (ECM) to change the camshaft timing of all 4 camshafts while the engine is operating. The CMP actuator assembly varies the camshaft position in response to directional changes in oil pressure. The CMP actuator solenoid controls the oil pressure that is applied to advance or retard a camshaft.

The CMP actuator assemblies have an outer housing that is driven by the engine timing chain. Inside the CMP assembly is a wheel with fixed vanes that is attached to the camshafts. The CMP actuator assemblies are also equipped with a locking pin. The locking pin prevents movement between the outer housing and the wheel vane assembly on engine start-ups. The CMP actuator is locked until sufficient oil pressure is available to control the CMP actuator. The locking pin is released by oil pressure before any movement in the CMP actuator assembly takes place.

Conditions for Running the DTC

    • DTCs P0010, P0013, P0020, P0023, P2088, P2089, P2090, P2091, P2092, P2093, P2094 and P2095 are not set.
    • The engine is operating for greater than 1 second.
    • The ECM completed the CMP actuator solenoid output driver test.
    • The engine speed is greater than 560 RPM.
    • DTCs P1011, P1012, P1013 and P1014 only run on an engine start-up.

Conditions for Setting the DTC

    • The ECM detects that the average of the actual camshaft angle measurements is greater than 10 degrees of the parked position angle on an engine start-up.
    • The condition exists for greater than 4 seconds, or a cumulative of 50 seconds.

Action Taken When the DTC Sets

DTCs P1011, P1012, P1013 and P1014 are type C DTCs.

Conditions for Clearing the DTC

DTCs P1011, P1012, P1013 and P1014 are type C DTCs.

Diagnostic Aids

    • Inform the customer that the following actions may cause DTCs P1011, P1012, P1013, or P1014 to set:
       - Turning the engine OFF while the accelerator pedal is pressed
       - Turning the engine OFF while driving
       - Pressing the accelerator pedal to start the engine
    • If the customers concern is that the engine is stalling, refer to Symptoms - Engine Controls for further diagnosis.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Air Intake System Description

Electrical Information Reference

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

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Ignition ON, clear the DTC information with a scan tool.
  2. Note: The engine oil level and the oil pressure are critical to the correct operation of the camshaft position (CMP) actuator system. Verify that the engine has the correct oil level and the correct oil pressure before continuing with this diagnostic. Refer to Fluid and Lubricant Recommendations and Oil Pressure Diagnosis and Testing.

  3. Start the engine. Verify there is no abnormal engine noise during start up. Observe the DTC information with a scan tool. DTC P1011, P1012, P1013, or P1014 should not set.
  4. If there is an abnormal engine noise, or a DTC set, replace the appropriate CMP actuator.
  5. 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.

Repair Instructions

Perform the Diagnostic Repair Verification.

    •  Camshaft Position Actuator Replacement - Bank 1 (Right Side) Intake
    •  Camshaft Position Actuator Replacement - Bank 1 (Right Side) Exhaust
    •  Camshaft Position Actuator Replacement - Bank 2 (Left Side) Intake
    •  Camshaft Position Actuator Replacement - Bank 2 (Left Side) Exhaust