GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The powertrain control module (PCM) uses the camshaft position (CMP) sensor high resolution signal in order to determine the position of the valve train in relation to the engine cylinders. The PCM uses the CMP high resolution signal in order to sequence the ignition system and the fuel injectors.

The PCM supplies a 12-volt reference and a low reference to the CMP sensor. The CMP sensor returns a signal pulse in response to the reluctor track, located on the camshaft sprocket. If the PCM detects an incorrect correlation between the CMP signal and the crankshaft position (CKP) signals, DTC P0341 will set.

Conditions for Running the DTC

The engine is running less than 2,000 RPM.

Conditions for Setting the DTC

The PCM detects an incorrect correlation between the CMP signal and the CKP signals.

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 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.

Diagnostic Aids

The following conditions may cause this DTC to set:

    • Damage to the camshaft sprocket
    • Incorrect sensor installation
    • The sensor coming in contact with the camshaft sprocket
    • Excessive air gap between the camshaft sprocket and the sensor
    • A cracked or damaged sensor
    • Foreign material passing between the sensor and the sprocket

If the condition is intermittent, refer to Intermittent Conditions .

Step

Action

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 - Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

Visually and physically inspect all circuits going to the camshaft position (CMP) sensor for the following conditions:

   • 

Being routed too close to secondary ignition wires or components

   • 

Being routed too close to after-market add-on electrical equipment

   • 

Being routed too close to solenoids, relays, and motors

If you find incorrect routing, correct the harness routing.

Did you find and correct the condition?

Go to Step 9

Go to Step 3

3

Test for an intermittent and for a poor connection at the CMP sensor. 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 9

Go to Step 4

4

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 9

Go to Step 5

5

  1. Remove the CMP sensor. Refer to Camshaft Position Sensor Replacement .
  2. Visually inspect the CMP sensor for the following conditions:
  3. • Physical damage
    • Excessive wear of the sensor
    • Loose or improper installation

Did you find and correct the condition?

Go to Step 9

Go to Step 6

6

Visually inspect the camshaft sprocket for damage.

If the camshaft sprocket is damaged refer to Camshaft Timing Drive Components Cleaning and Inspection in Engine Mechanical.

Did you find and correct the condition?

Go to Step 9

Go to Step 7

7

Replace the CMP sensor. Refer to Camshaft Position Sensor Replacement .

Did you find and correct the condition?

Go to Step 9

Go to Step 8

8

Replace the PCM. Refer to Powertrain Control Module Replacement .

Did you find and correct the condition?

Go to Step 9

Go to Diagnostic Aids

9

  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 10

10

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

Go to Diagnostic Trouble Code (DTC) List

System OK