P0340 - Camshaft Position (CMP) Sensor Circuit Malfunction ,did you check the wiring ?
P0340 - Camshaft Position (CMP) Sensor Circuit Malfunction
The test fails when the PCM can no longer detect the signal from the CMP sensor.
- CMP circuit open
- CMP circuit short to GND
- CMP circuit short to PWR
- SIG RTN open (VR sensor)
- CMP GND open (Hall effect sensor)
- CMP misinstalled (Hall effect sensor)
- Damaged CMP sensor shielding
- Damaged CMP sensor
- Damaged PCM
Harness routing, harness alterations, improper shielding, or electrical interference from other improperly functioning systems may have intermittent impact on the CMP signal.
DR1 DTC P0340: CHECK IF ENGINE WILL START
Note: Refer to the Pinpoint Test Schematic to determine the type of CMP sensor.
- Start engine.
Will the engine start?
GO to DR2 .
DTC P0340 is not the cause of the No Start. GO to Section 3 to diagnose the No Start symptom.
Is the PCM firing the injectors ?
Extended cranking because of a no start can load the exhaust system with raw fuel, damaging the catalytic converter after the engine starts. For applications with Secondary Air Injection (AIR) Systems, perform the following after the no start has been repaired: Disconnect the electric secondary air injection (AIR) solid state relay, run the engine until the surplus fuel is used up, and reconnect the relay (disconnecting the relay may set a Continuous Memory PCM DTC that will need to be cleared).
REFERENCE (Section 5 Pinpoint Test unless noted)
- Add-on Anti-Theft Devices
- Visual, check with customer.
- For LS6/LS8:
- GO to KB85 .
- All others:
- GO to A1 .
- If engine is now a no start:
- If engine will start and run normally at part throttle, check Idle Air Control (IAC) System.
- Engine will now start and run normally at part throttle:
- GO to KE2
- Exhaust System (restrictions)
- Engine System - General Information Section 303-00 of the Workshop Manual.