P0340
DTC P0340
DTC DESCRIPTORS
DTC P0016
Camshaft Position (CMP) Sensor Performance
DTC P0340
Camshaft Position (CMP) Sensor Circuit
DIAGNOSTIC FAULT INFORMATION
IMPORTANT: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Testing and Inspection
CIRCUIT/SYSTEM DESCRIPTION
The camshaft position (CMP) sensor correlates the crankshaft to camshaft position so that the engine control module (ECM) can determine which cylinder is ready to be fueled 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. The CMP sensor circuits are directly connected to the ECM. The CMP sensor also determines which cylinder is misfiring. The CMP sensor circuits consist of the following:
- An ignition 1 voltage
- A low reference
- A CMP signal
CONDITIONS FOR RUNNING THE DTC
- DTCs P0335 and P0336 are not set.
- The engine is running.
- The DTCs run continuously once the above conditions are met.
CONDITIONS FOR SETTING THE DTC
P0016
The ECM detects an incorrect CMP signal for more than 10 crankshaft revolutions.
P0340
The ECM detects no CMP signal for more than 1 second.
ACTION TAKEN WHEN THE DTC SETS
DTCs P0016 and P0340 are Type A DTCs.
CONDITIONS FOR CLEARING THE DTC
DTCs P0016 and P0340 are Type A DTCs.
DIAGNOSTIC AIDS
The following conditions can also set the DTC:
- Physical damage to the CMP sensor or the reluctor wheel
- Excessive play or looseness of the CMP sensor or the reluctor wheel
- Improper installation of the CMP sensor or the reluctor wheel
- Foreign material passing between the CMP sensor and the reluctor wheel
- Excessive air gap between the CMP sensor and the reluctor wheel
CIRCUIT/SYSTEM VERIFICATION
1. Start the engine, observe the DTC information with a scan tool. DTCs P0016 and P0340 should not set.
2. If the vehicle passes the Circuit/System Verification Test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records List.
CIRCUIT/SYSTEM TESTING
1. Ignition OFF, disconnect the harness connector of the CMP sensor.
2. Connect a test lamp between the ignition 1 voltage circuit of the CMP sensor and the negative terminal of the battery.
IMPORTANT: The test lamp is used to load the circuit and may not illuminate.
3. Ignition ON, test for less than 0.5 volt between the ignition 1 voltage circuit of the CMP sensor and the positive terminal of the battery.
- If greater than 0.5 volt, repair the ignition 1 voltage circuit of the CMP sensor for a short to ground or an open/high resistance.
4. Connect a test lamp between the ground circuit and the ignition 1 voltage circuit of the CMP sensor.
- If the test lamp does not illuminate, test for an open/high resistance on the ground circuit. If circuit/connections test normal, replace the ECM.
5. Ignition OFF, connect a DMM between the signal circuit and the low reference circuit of the CMP sensor.
6. Ignition ON, verify that 4.8-5.2 volts is available on the signal circuit and the low reference circuit of the CMP sensor.
- If less than 4.8 volts, test the signal circuit for a short to ground or an open/high resistance. If the circuits/connections test normal, replace the ECM.
- If more than 5.2 volts, test the signal circuit for a short to voltage. If the circuits/connections test normal, replace the ECM.
7. If all circuits/connections test normal, replace the CMP sensor.
REPAIR INSTRUCTIONS
IMPORTANT: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests