Circuit Description
The Camshaft Position (CMP) Sensor indicates the camshaft position so that the Powertrain Control Module (PCM) can determine which cylinder is misfiring when a misfire is present. Whenever the PCM receives an intermittent signal from the CMP, then the CMP Resync Counter will increment. In order to set a DTC, the PCM must see a minimum number of resync's within a maximum time.
Conditions for Setting the DTC
| • | The engine is running. |
| • | The CMP resync counter increments more than 15 counts in less than 256 seconds. |
Action Taken When the DTC Sets
| • | The malfunction indicator lamp (MIL) will illuminate. |
| • | The PCM will record the operating conditions at the time that the diagnostic fails. The Freeze Frame and Failure Records buffers will store this information. |
| • | A history DTC stores. |
Conditions for Clearing the MIL/DTC
| • | The malfunction indicator lamp (MIL) will turn OFF after 3 consecutive ignition cycles in which the diagnostic runs without a fault. |
| • | A history DTC will clear after 40 consecutive warm up cycles without a fault. |
| • | Use a scan tool to clear the DTCs. |
Diagnostic Aids
| • | A poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation may cause an intermittent problem. |
| • | Thoroughly check any circuitry, that is suspected as causing the intermittent complaint, for the following conditions: |
| - | Improper mating |
| - | Broken locks |
| - | Improperly formed or damaged terminals |
| - | Physical damage to the wiring harness |
| • | Whenever the PCM sees less than 15 resyncs in 256 seconds, the counter is reset to 0. Anytime a poor connection is present, the Cam Sensor Reference Activity counter will stop incrementing and the Cam Sensor Resync Counter will increment. |
Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table.
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The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data taken when the malfunction occurred. The information is then stored on the scan tool for later reference.
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This step determines if DTC P0341 is the result of a hard malfunction or an intermittent condition.
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The counter should stop incrementing with the sensor electrical connector disconnected and set a DTC P0342 after two ignition cycles with the sensor disconnected. If it stills increments then the PCM is malfunctioning.
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By moving the CMP sensor electrical connector, the connections at the sensor are checked. Make sure electrical connector remains securely fastened.
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A poor connection in any of the circuits at the CMP sensor will cause the CMP Resync Counter to increment. Anytime a poor connection is present, the CMP Reference Activity counter will stop incrementing and the CMP Resync Counter will increment.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | Go to | ||
Is the CMP Resync Counter incrementing? | -- | |||
Disconnect the Camshaft Position (CMP) sensor electrical connector. Did the CMP Resync Counter stop incrementing? | -- | |||
With the engine still running, wiggle the CMP sensor electrical connector by hand. Did the CMP Resync Counter start to increment? | -- | |||
Check for a poor connection at the CMP sensor electrical connector and repair as necessary. Was a repair necessary? | -- | |||
6 | Replace the PCM. Refer to Powertrain Control Module Replacement/Programming . Is the action complete? | -- | -- | |
7 | Replace the Camshaft Position (CMP) sensor. Refer to Camshaft Position Sensor Replacement . Is the action complete? | -- | -- | |
8 |
Is the CMP Resync Counter incrementing? | -- | ||
9 |
Does the scan tool indicate that this diagnostic has ran and passed? | -- | ||
10 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | -- | Go to applicable DTC table | System OK |
