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For 1990-2009 cars only
Table 1: CMP Actuator Authority Table

Circuit Description

The camshaft position (CMP) actuator system is comprised of four CMP actuator solenoids, four oil control valves, and four 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 camshaft position relative to the crankshaft position.

CMP Actuator Authority Table

Camshaft position relative to crankshaft position

Crankshaft position when the intake or exhaust valve begins to open with camshaft actuators in park.

Crankshaft position when the intake or exhaust valve begins to open with camshaft actuators at full travel.

Intake Camshafts

133° ATDC (CMP actuator position is at 0° on scan tool).

93° ATDC (CMP actuator position is at 40° on scan tool)

Exhaust Camshafts

117° BTDC (CMP actuator position is at 0° on scan tool)

67° BTDC (CMP actuator position is at 50° on scan tool)

If the desired camshaft position does not match the actual camshaft position for a calibrated amount of time, DTC P0011, P0014, P0021 or P0024 will set.

Conditions for Running the DTC

    • DTCs P0010, P0011, P0013, P0014, P0016, P0017, P0018, P0019, P0020, P0021, P0023, P0024, 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 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.
    • The calculated engine oil temperature is between -10 to +150°C (14-302°F)
    • The ignition voltage is between 11-16 volts.

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.
    • The above condition exists for more than 16 seconds.

Action Taken When the DTC Sets

    • The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

The CMP actuator system will be disabled until the end of 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

Values

Yes

No

Schematic Reference: Engine Controls Schematics

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

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  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 3

Go to Intermittent Conditions

3

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

Did you find and correct the condition?

 

Go to Step 11

Go to Step 4

4

  1. Disconnect the affected CMP actuator solenoid.
  2. Measure the resistance of the CMP actuator solenoid with a DMM.

Is the resistance within the specified value for the specified CMP actuator solenoid temperature?

3.26-3.66 ohms at -40°C (-40°F)

4.00-4.50 ohms at 20°C (68°F)

4.02-4.52 ohms at 25°C (77°F)

5.68-6.38 ohms at 125°C (257°F)

Go to Step 5

Go to Step 9

5

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

Did you find and correct the condition?

--

Go to Step 11

Go to Step 6

6

  1. Disconnect the ECM.
  2. Test the control circuit of the affected CMP actuator solenoid for resistance that is more than the specified value. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

2.5 ohms

Go to Step 11

Go to Step 7

7

Test the ground circuit of the affected CMP actuator solenoid for resistance that is more than the specified value. Refer to Ground Distribution Schematics and to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

2.5 ohms

Go to Step 11

Go to Step 8

8

Test for the following conditions:

    • Degraded oil quality and proper oil level
    • Low engine oil pressure--Refer to Oil Pressure Diagnosis and Testing in Engine Mechanical.
    • Oil pressure leaks and restrictions in the dedicated oil passages from the oil filter to the affected CMP actuator--Refer to Oil Pump Outlet Tube Cleaning and Inspection .
    • A slow moving or sticking oil control valve--Refer to Camshaft Timing Drive Components Cleaning and Inspection in Engine Mechanical.
    • A slow moving or sticking CMP actuator--Refer to Camshaft Timing Drive Components Cleaning and Inspection in Engine Mechanical.
    • A loose primary or secondary timing chain--Refer to Camshaft Timing Drive Components Cleaning and Inspection in Engine Mechanical.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 10

9

Replace the affected CMP actuator solenoid. Refer to 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 , or Camshaft Position Actuator Solenoid Valve Solenoid Replacement - Bank 2 (Left Side) Exhaust .

Did you complete the replacement?

--

Go to Step 11

--

10

Replace the ECM. Refer to Engine Control Module Replacement .

Did you complete the replacement?

--

Go to Step 11

--

11

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Operate the vehicle with in the Conditions for Running the DTC. You may also operate the vehicle with in the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 12

12

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