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 Bank 1

DTC P0014: Exhaust Camshaft Position (CMP) System Performance Bank 1

DTC P0021: Intake Camshaft Position (CMP) System Performance Bank 2

DTC P0024: Exhaust Camshaft Position (CMP) System Performance Bank 2

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

Intake CMP Actuator Solenoid Control Circuit Bank 1

P0010, P0011

P0010

P0010

P0010, P0011

--

Exhaust CMP Actuator Solenoid Control Circuit Bank 1

P0013, P0014

P0013, P0014

P0013

P0013, P0014

--

Intake CMP Actuator Solenoid Control Circuit Bank 2

P0020, P0021

P0020, P0021

P0020

P0020, P0021

--

Exhaust CMP Actuator Solenoid Control Circuit Bank 2

P0023, P0024

P0023, P0024

P0023

P0023, P0024

--

Intake CMP Actuator Solenoid Low Reference Circuit Bank 1

--

P0010, P0011

P0010

--

--

Exhaust CMP Actuator Solenoid Low Reference Circuit Bank 1

--

P0013, P0014

P0013

--

--

Intake CMP Actuator Solenoid Low Reference Circuit Bank 2

--

P0020, P0021

P0020

--

--

Exhaust CMP Actuator Solenoid Low Reference Circuit Bank 2

--

P0023, P0024

P0023

--

--

Circuit/System Description

The camshaft position (CMP) actuator system is comprised of 4 CMP actuator solenoids, 4 oil control valves, and 4 CMP actuators. The engine control module (ECM) sends an electrical signal to the CMP actuator solenoids through the control circuits when a camshaft timing change is desired. The ground circuits of the CMP actuator solenoids are used as a return. The CMP actuator solenoid uses electromagnetic force to pull on the plunger of the oil control valve. The oil control valve will port the pressurized engine oil to either the advancing or retarding chambers of the CMP actuator. The CMP actuator, in turn, changes the CMP relative to the crankshaft position (CKP). If the desired CMP does not match the actual CMP for a calibrated amount of time, DTC P0011, P0014, P0021, or P0024 will set.

Conditions for Running the DTC

    • DTCs P0010, P0013, P0016, P0017, P0018, P0019, P0020, P0023, , P0335, P0336, P0340, P0341, P0345, P0346, P0365, P0366, P0390, P0391, P2088, P2089, P2090, P2091, P2092, P2093, P2094, P2095 are not set.
    • The CMP actuators are commanded.
    • The engine oil pressure (EOP) is between 100-696.4 kPa (14.5-101 psi).
    • The engine speed is at an RPM between 1,000-6,500 RPM, that will allow for steady activation of the cam actuators based on calculated engine oil temperature (EOT).
    • The calculated EOT is between -10 to +150°C (+14 to +302°F).
    • The ignition voltage is between 9-18 volts.
    • DTC P0011, P0014, P0021, or P0024 runs continuously when the above conditions are met.

Conditions for Setting the DTC

The ECM detects the difference between the desired camshaft position and the actual camshaft position angles is more than 6 degrees for more than 1.6 seconds.

Action Taken When the DTC Sets

DTCs P0011, P0014, P0021, and P0024 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P0011, P0014, P0021, and P0024 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
    •  Lubrication 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. Observe the engine oil level. The engine oil level should be within the operating range on the oil indicator stick.
  2. Start the engine; allow the engine to reach normal operating temperature.
  3. Using the scan tool monitor the engine oil pressure parameter value. The engine oil pressure must be at or above the minimum hot oil pressure values. Refer to Engine Mechanical Specifications.
  4. Important: The CMP Actuator Output Control function will automatically raise the engine speed.

  5. Using the output control function of the scan tool, command the CMP actuator solenoid to 20 degrees. The CMP Desired parameter value should match the CMP Angle parameter value.
  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

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

    Important: Incorrect engine oil viscosity, aftermarket engine oil additives, or engine oil that overdue for changing, can greatly affect the performance of the camshaft actuator.

  1. Ignition OFF and scan tool disconnected for 90 seconds, disconnect the appropriate CMP actuator solenoid harness connector at the appropriate CMP actuator solenoid.
  2. Test for less than 5 ohm between the low reference circuit terminal B and ground.
  3. If greater than 5 ohms, test the low reference for an open/high resistance. If the circuit tests normal replace the ECM.
  4. Test for less than 1 ohm of resistance on the control circuit.
  5. If greater than 1 ohm, test the control circuit for an open/high resistance. If the circuit tests normal replace the ECM.
  6. Inspect the CMP actuator. Refer to Camshaft Position Actuator Housing Cleaning and Inspection.
  7. Inspect the engine timing components. Refer to Camshaft Timing Drive Chain Alignment Diagram.

Component Testing

Static Test

  1. Ignition OFF, disconnect the appropriate CMP actuator solenoid harness connector at the CMP actuator solenoid.
  2. Test for 2-12 ohms of resistance at 25°C (77°F) between the control terminal B and the low reference terminal A of the CMP actuator solenoid.
  3. If the resistance is not within the specified range, replace the CMP actuator solenoid.

Dynamic Test

    Important: Do not allow the solenoid to be energized for more than 2 seconds.

  1. Install a fused jumper wire between the control terminal B and 12 volts. Install a jumper wire between the low reference terminal A and momentarily connect to ground.
  2. Listen for the solenoid to click.
  3. If the function does not perform as specified, replace the CMP actuator solenoid.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Control Module References for ECM replacement, setup, and programming
    •  Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Intake
    •  Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 1 (Right Side) Exhaust
    •  Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Intake
    •  Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Exhaust
    •  Camshaft Timing Drive Components Cleaning and Inspection