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 P0010: Intake Camshaft Position (CMP) Actuator Solenoid Control Circuit

DTC P0013: Exhaust Camshaft Position (CMP) Actuator Solenoid Control Circuit

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Intake CMP Actuator Solenoid Control

P0010

P0010

P0010

P0011

Exhaust CMP Actuator Solenoid Control

P0013

P0013

P0013

P0014

Intake CMP Actuator Solenoid Low Reference

--

P0010, P0011

--

P0011

Exhaust CMP Actuator Solenoid Low Reference

--

P0013, P0014

--

P0014

Circuit/System Description

The camshaft position (CMP) actuator system enables the engine control module (ECM) to change the timing of the camshafts while the engine is operating. The ECM supplies a low reference circuit, and a pulse width modulated (PWM) control circuit to the CMP actuator solenoid. The ECM controls the CMP actuator solenoid duty cycle by controlling the amount of solenoid ON time. The CMP actuator solenoid controls the advance or the retard of each camshaft. The CMP actuator solenoid controls the oil flow that applies the pressure to advance or retard the camshafts.

The ECM controls the solenoid with a solid state device called a driver. The driver is equipped with a feedback circuit that is pulled-up to a voltage. The ECM can determine if the control circuit is open, shorted to ground, or shorted to a voltage by monitoring the feedback voltage.

Conditions for Running the DTC

    • The engine is operating.
    • The ignition voltage is between 11-18 volts.
    • The CMP actuator is commanded ON.
    • The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for greater than 5 seconds.

Action Taken When the DTC Sets

DTCs P0010 and P0013 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0010 and P0013 are Type B DTCs.

Diagnostic Aids

If the condition is intermittent, move the related harnesses and connectors, with the engine operating, while monitoring the scan tool CMP solenoid circuit status parameters. The circuit status parameters will change from OK, or Not Run, to Fault if there is a condition with the circuit or connection.

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

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, command the appropriate CMP Actuator ON and OFF with a scan tool. You should hear the solenoid click when commanded ON and OFF.
  2. Engine idling, observe the following scan tool control circuit status parameters:
  3. • CMP Sol Ckt Short Gnd Test Status
    • CMP Sol Ckt Open Test Status
    • CMP Sol Ckt Short Volts Test Status
    • Each parameter should display OK or Not Run.
  4. 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.

Circuit/System Testing

  1. Ignition OFF for 1 minute, disconnect the harness connector at the appropriate camshaft position (CMP) actuator solenoid.
  2. Test for less than 5 Ω between the low reference circuit terminal 2 and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
  4. Ignition ON, test for 2-3 V between the control circuit terminal 1 and ground.
  5. If less than the specified range, test the control circuit for a short to ground, or an open/high resistance. If the circuit tests normal, replace the ECM.
    If greater than the specified range, test the control circuit for a short to voltage. If the circuit/connections test normal, replace the ECM.
  6. Command the CMP actuator solenoid ON and OFF with a scan tool. The DMM should transition from 2-3 V when commanded OFF to greater than 10 V, when commanded ON.
  7. If the circuit voltage does not correspond to the specified values, replace the ECM.
  8. If all circuits/connections test normal, test or replace the CMP actuator solenoid.

Component Testing

  1. Ignition OFF, disconnect the harness connector at the appropriate CMP actuator solenoid.
  2. Test for 7-12 Ω between the terminals of the CMP actuator solenoid.
  3. If not within the specified range, replace the CMP actuator solenoid.
  4. Test for infinite resistance between each terminal and the CMP actuator solenoid housing.
  5. If not the specified value, replace the CMP actuator solenoid valve.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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