P0340

DTC P0340

Circuit Description

The intake camshaft position (CMP) sensor is a hall integrated circuit (IC) type sensor that works in conjunction with an eight tooth reluctor wheel used to determine the position of the intake camshaft. The engine control module (ECM) supplies a 12-volt pull up voltage on the CMP sensor signal circuit. As the teeth on the reluctor wheel passes the CMP sensor, it sends a digital signal which is an image of the reluctor wheel to the ECM. The ECM processes this information to determine the exact position of the camshafts, and to determine the optimum ignition and injection points of the engine. The CMP sensor wiring consists of a 12-volt reference circuit, a low reference circuit and a signal circuit. If the ECM cannot see a change in the intake CMP sensor signal DTC P0340 or P0345 will set.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

The ECM does not detect a signal from the Intake CMP sensor after 10 seconds of engine run time.

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 reluctor wheel
- Damage to the CMP sensor
- The sensor coming in contact with the reluctor wheel
- Foreign material passing between the sensor and the reluctor wheel

If the condition is intermittent.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

2. This step verifies that the condition is present.
6. This step determines if the signal circuit is shorted to voltage. A normal operating signal circuit will not illuminate a test lamp.