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For 1990-2009 cars only

Circuit Description

Each camshaft is equipped with a camshaft position (CMP) sensor that the engine control module (ECM) monitors. The CMP sensor is a hall effect switch that works in conjunction with a 4X reluctor wheel. The reluctor wheels are mounted to the camshaft position actuators that are mounted to the end of the camshafts. The ECM uses the CMP sensor signals in order to determine the position of the camshafts.

The ECM supplies 5 volts to the CMP sensors on the 5-volt reference circuits, and supplies a ground on the low reference circuits. The CMP sensors provide a signal to the ECM on the signal circuits. If the ECM detects extra or missing CMP sensor signal transitions within a certain number of crankshaft revolutions, this DTC sets.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC P0341 Intake Camshaft Position (CMP) Sensor Performance Bank 1
    • DTC P0346 Intake Camshaft Position (CMP) Sensor Performance Bank 2
    • DTC P0366 Exhaust Camshaft Position (CMP) Sensor Performance Bank 1
    • DTC P0391 Exhaust Camshaft Position (CMP) Sensor Performance Bank 2

Conditions for Running the DTC

DTCs P0341, P0346, P0366, and P0391 run continuously once the engine is operating for more than 1 second.

Conditions for Setting the DTC

    • The ECM detects a signal from the CMP sensor, but the number of pulses are at least 5 less than or more than what is expected for one crankshaft revolution.
        OR
    • The CMP sensor does NOT correlate to the crankshaft position.
    • Either condition exists for more 4 seconds.

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.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (MIL) after 4 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.

Diagnostic Aids

The following table illustrates the ECM connector locations:

ECM Connector Location

C2

C1

Front of Vehicle

    • Use the J 35616-A/BT-8637 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector.
    • For an intermittent condition, refer to Intermittent Conditions .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step verifies that the condition is present.

  2. This step inspects for electromagnetic interference (EMI) on the CMP sensor circuits.

Step

Action

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

2

  1. Turn ON the ignition, with the engine OFF.
  2. Clear the DTCs with a scan tool.
  3. Start the engine.
  4. Observe the DTC information with a scan tool.

Does DTC P0341, P0346, P0366, or P0391 fail this ignition?

Go to Step 3

Go to Step 4

3

Did DTC P0342, P0343, P0347, P0348, P0367, P0368, P0392, or P0393 also fail this ignition cycle?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

Go to Step 5

4

  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 5

Go to Diagnostic Aids

5

Inspect the circuit of the camshaft position (CMP) sensor for the following conditions:

    • Routed too close to the ignition coils
    • Routed too close to after-market add-on electrical equipment
    • Routed too close to solenoids, relays, and motors

If you find an incorrect routing, correct the harness routing.

Did you find and correct the condition?

Go to Step 10

Go to Step 6

6

Test for an intermittent and for a poor connection at the appropriate CMP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 10

Go to Step 7

7

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 Connector Repairs .

Did you find and correct the condition?

Go to Step 10

Go to Step 8

8

  1. Remove the appropriate CMP sensor.
  2. Inspect the CMP sensor and the camshaft actuator reluctor wheel for the following conditions:
  3. • Incorrect sensor installation
    • A cracked or damaged sensor
    • The sensor coming in contact with the reluctor wheel
    • Excessive air gap between the reluctor wheel and the sensor
    • Foreign material passing between the sensor and the camshaft reluctor wheel
    • Camshaft reluctor wheel damage

Did you find and correct the condition?

Go to Step 10

Go to Step 9

9

Replace the CMP sensor. Refer to the appropriate procedure:

Did you complete the replacement?

Go to Step 10

--

10

  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 11

11

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

System OK