DTC Advanced Diagnostics: P0340
DTC P0340:Camshaft Position (CMP) Sensor A No Signal

General Description

Camshaft position (CMP) sensor A consists of a rotor and a semiconductor that detects rotor position and intake camshaft timing. When the rotor turns after starting the engine, the changes of magnetic flux in the semiconductor are converted into pulsing signals to the powertrain control module (PCM). CMP sensor A also detects the top dead center of each cylinder for fuel injection. The PCM determines the camshaft position according to the signals from the crankshaft position (CKP) sensor and CMP sensor A. If no pulsing signals from CMP sensor A are detected, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type
Execution
Continuous
Sequence
None
Duration
2 seconds or more (when the engine speed is 750 min-1 (rpm))
DTC Type
One drive cycle, MIL on

Enable Conditions
Condition
  
State of the engine
Running

Malfunction Threshold
No input signals from CMP sensor A are detected while signals from the CKP sensor are detected at least 300 times.

Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
CMP sensor A TDCAM line open
CMP sensor A TDCAM line short to ground
CMP sensor A VCC line open
CMP sensor A SG line open
CMP sensor A failure
PCM internal circuit failure

Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected, the MIL comes on and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.