GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The camshaft position (CMP) sensor correlates the crankshaft to camshaft position so that the engine control module (ECM) can determine which cylinder is ready to be fueled by an injector. As the camshaft rotates, the reluctor wheel interrupts a magnetic field produced by a magnet within the sensor and sends a signal to the ECM through the signal circuit. The CMP sensor circuits are directly connected to the ECM. The CMP sensor also determines which cylinder is misfiring. The CMP sensor circuits consists of the following:

    • An ignition 1 voltage
    • A low reference
    • A CMP signal

If the ECM detects an incorrect CMP sensor signal, DTC P0341 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0341 Camshaft Position (CMP) Sensor Performance

Conditions for Running the DTC

    • The engine is running
    • DTC P0341 runs continuously when the above condition is met.

Conditions for Setting the DTC

The ECM detects an incorrect CMP signal for more than 10  crankshaft revolutions.

Action Taken When the DTC Sets - European Emissions

    • The malfunction indicator lamp (MIL) will illuminate after 3 consecutive trips with a fail.
    • The ECM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records buffers.

Action Taken When the DTC Sets - Non European Emissions

The malfunction indicator lamp (MIL) will illuminate.

Conditions for Clearing the MIL/DTC - European Emissions

    • The MIL will turn OFF after 4 consecutive ignition cycles in which the diagnostic runs without a fault.
    • DTCs can be cleared by using the scan tool.
    • Disconnect the ECM battery feed for more than 10 seconds.

Conditions for Clearing the MIL/DTC - Non European Emissions

    • The MIL will turn OFF after the diagnostic runs without a fault.
    • DTCs can be cleared by using the scan tool.
    • Disconnect the ECM battery feed for more than 10 seconds.

Step

Action

Yes

No

Schematic Reference: Engine Controls Schematics

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

1

Did you perform the Diagnostic System Check - Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

  1. Start the engine
  2. Observe the DTC Information with a scan tool.

Did DTC P0341 fail this ignition?

Go to Step 4

Go to Step 3

3

  1. Turn OFF the ignition for 30 seconds.
  2. Start the engine.
  3. Operate the vehicle within the Conditions for Running the DTC.

Did the DTC fail this ignition?

Go to Step 4

Go to Intermittent Conditions

4

  1. Turn OFF the ignition.
  2. Inspect the camshaft position (CMP) sensor circuits for the following conditions:
  3. • Routed too close to other wiring or components
    • Routed too close to after market add on electrical equipment
    • Routed too close to solenoids, relays, and motors
    • Electromagnetic interference in the CMP sensor circuits

Did you find and correct the condition?

Go to Step 11

Go to Step 5

5

Test the CMP sensor circuits for an intermittent condition. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 6

6

Test for an intermittent and for a for poor connection at the ECM. 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 11

Go to Step 7

7

Test for an intermittent and for a for poor connection at the CMP connector. 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 11

Go to Step 8

8

  1. Remove the CMP sensor. Refer to Camshaft Position Sensor Replacement .
  2. Inspect the CMP sensor for the following conditions:
  3. • Physical damage
    • Excessive play or looseness
    • Improper installation
    • Foreign material passing between the CMP sensor and the reluctor wheel
    • Excessive air gap between the CMP sensor and the reluctor wheel

Did you find and correct the condition?

Go to Step 11

Go to Step 9

9

Important: If the reluctor wheel is damaged, replace the CMP sensor.

Inspect the reluctor wheel for the following conditions:

    • Physical damage
    • Improper installation
    • Excessive end play or looseness

Did you find and correct the condition?

Go to Step 11

Go to Step 10

10

Replace the CMP sensor. Refer to Camshaft Position Sensor 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. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC.

Did the DTC fail this ignition?

Go to Step 2

Go to Step 12

12

Are there any DTCs that have not been diagnosed?

Go to Diagnostic Trouble Code (DTC) List

System OK