Circuit Description
The camshaft position (CMP) sensor is a 1X sensor. It provides 1 digital ON/OFF signal to the powertrain control module (PCM) per revolution of the camshaft. This information is used by the PCM to determine the position of the valve train relative to the crankshaft position (CKP). By monitoring the CMP and the CKP signals, the PCM can accurately time the operation of the fuel injectors. The CMP sensor is connected directly to the ignition control module (ICM). The sensor wiring includes the following circuits that are shared with the CKP sensor:
| • | The CMP sensor signal circuit |
| • | A 12-volt reference circuit |
| • | A low reference circuit |
The signal is passed through the ICM to the PCM on the camshaft position signal circuit. The PCM monitors the CMP sensor for errors. If the PCM receives an incorrect number of signals from the CMP sensor, 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 run time is more than 3 seconds. |
| • | This diagnostic runs continuously when the above condition is met. |
Conditions for Setting the DTC
| • | The PCM detects the following for every two engine revolutions: |
| - | 36 medium resolution engine speed signals |
| - | 6 low resolution engine speed signals |
| - | More than 1 camshaft position signal |
| • | The condition is met for more than 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 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: |
| - | Camshaft reluctor ring damage |
| - | The sensor coming in contact with the reluctor ring |
| - | Foreign material passing between the sensor and the reluctor ring |
| - | Wear or damage to the timing chain or sprickets--Refer to Camshaft Timing Chain and Sprocket Cleaning and Inspection . |
| - | Excessive camshaft end-play |
| - | Wiring routed too close to secondary ignition components |
| • | If you suspect the condition is intermittent, refer to Testing for Intermittent Conditions and Poor Connections . |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step inspects for electromagnetic interference (EMI) on the CMP sensor circuits.
-
Damage to the face of the sensor could indicate foreign material passing between the CMP sensor and the reluctor wheel. This condition would cause this DTC to set. Damage to the reluctor wheel would affect the CMP sensor output.
Step | Action | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module Connector End Views | |||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |||||||
2 |
Did the DTC fail this ignition? | Go to Step 3 | Go to Diagnostic Aids | ||||||
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 CMP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 9 | Go to Step 5 | ||||||
5 | 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 . Did you find and correct the condition? | Go to Step 9 | Go to Step 6 | ||||||
Did you find and correct the condition? | Go to Step 9 | Go to Step 7 | |||||||
7 |
Did you find and correct the condition? | Go to Step 9 | Go to Step 8 | ||||||
8 | Replace the CMP sensor. Refer to Camshaft Position Sensor Replacement . Did you complete the replacement? | Go to Step 9 | -- | ||||||
9 |
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? | System OK | |||||||
