DTC P0340
Diagnostic Instructions
DTC Descriptor
DTC P0340 28: Camshaft Position Sensor Circuit Incorrect Frequency
DTC P0340 29: Camshaft Position Sensor Circuit Too Few Pulses
Circuit/System Description
The camshaft position sensor correlates the crankshaft to camshaft position so that the engine control module (ECM) can determine which cylinder is ready to be fuelled 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.
Conditions for Running the DTC
| • | DTCs P0016, P0335 and P0336 are not set. |
| • | The engine speed is greater than 50 RPM. |
| • | The DTCs run continuously once the above conditions are met. |
Conditions for Setting the DTC
The ECM detects too few, or an incorrect amount, of CMP pulses.
Action Taken When the DTC Sets
DTC P0340 is a Type B DTC.
Conditions for Clearing the DTC
DTC P0340 is a Type B DTC.
Diagnostic Aids
The following conditions can also set the DTC:
| • | Physical damage to the camshaft position sensor or the reluctor wheel |
| • | Excessive play or looseness of the crankshaft position sensor or the reluctor wheel |
| • | Improper installation of the camshaft position sensor or the reluctor wheel |
| • | Foreign material passing between the camshaft position sensor and the reluctor wheel |
| • | Excessive air gap between the crankshaft position sensor and the reluctor wheel |
Reference Information
Schematic Reference
Engine Controls Schematics : LLW
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Engine running, observe the DTC information with a scan tool. DTC P0340 should not set.
- Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the B23 Camshaft Position Sensor.
- Test for less than 5 Ω between the low reference circuit terminal 2 and ground.
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit/connections test normal, replace the K20 Engine Control Module. |
- Ignition ON, verify that a test lamp illuminates between the ignition 1 voltage circuit terminal 3 and ground.
| ⇒ | If the test lamp does not illuminate, test the ignition voltage 1 circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition 1 voltage circuit fuse is open, test all components connected to the ignition 1 voltage circuit and replace as necessary. |
- Ignition On, test for 4.8 - 5.2 V between the signal circuit terminal 1 and ground.
| ⇒ | If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
| ⇒ | If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module. |
- If all circuits test normal, test or replace the B23 Camshaft Position Sensor.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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