GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The camshaft position (CMP) actuator is controlled by the powertrain control module (PCM) through a high control circuit and a low reference circuit. The high control circuit carries a 12-volt pulse width modulated (PWM) signal from the PCM to the CMP actuator solenoid in order to control the amount of engine oil flow to the cam phaser. The low reference circuit is used as a return circuit. The PCM has the ability to monitor the functionality of the high control and the low reference circuit. If the PCM detects an open, short to ground, or a short to voltage, DTC P0013 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

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

Conditions for Running the DTC

    • The engine is running.
    • DTC P0013 runs continuously when the engine is running.

Conditions for Setting the DTC

The PCM detects an open, short to ground, or a short to voltage in the high control circuit of the CMP actuator solenoid or an open in the low reference circuit of the CMP actuator solenoid for more than 0.25 second.

Action Taken When the DTC Sets

    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

The PCM disables the cam phaser for the ignition cycle.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Step

Action

Value(s)

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Start the engine
  2. Allow the engine to reach operating temperature.
  3. Increase the engine speed to 1,500 RPM.
  4. Command the cam phaser to 90 percent with a scan tool.

Does the Cam Phase Actual parameter match the Cam Phase Angle Desired parameter?

--

Go to Step 3

Go to Step 4

3

  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. 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.

Did the DTC fail this ignition?

--

Go to Step 4

Go to Intermittent Conditions

4

  1. Turn OFF the ignition.
  2. Disconnect the camshaft position (CMP) actuator solenoid.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage from the CMP actuator solenoid high control circuit to a good ground with a DMM.

Is the voltage less than the specified value?

B+

Go to Step 7

Go to Step 5

5

Connect a test lamp between the CMP actuator solenoid high control circuit and a good ground.

Does the test lamp illuminate?

--

Go to Step 9

Go to Step 6

6

Connect a test lamp between the low reference circuit of the CMP actuator solenoid and B+.

Does the test lamp illuminate?

--

Go to Step 11

Go to Step 8

7

Test the CMP actuator solenoid high control circuit for an open or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 14

Go to Step 10

8

Test the low reference circuit of the CMP actuator solenoid for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 14

Go to Step 10

9

Test the CMP actuator solenoid high control circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 14

Go to Step 12

10

Test for an intermittent and for a poor connection at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 14

Go to Step 12

11

Test for an intermittent and for a poor connection at the CMP actuator solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 14

Go to Step 13

12

Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 14

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13

Replace the CMP actuator solenoid. Refer to Camshaft Position Actuator Solenoid Valve Replacement .

Did you complete the replacement?

--

Go to Step 14

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14

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. 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.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 15

15

Observe the capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information

System OK