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

General Description

The camshaft position sensoring operates based on pulse detection and counting. The fundamental components are a pulse plate mounted on the end of the shaft (rotary part) and camshaft position (CMP) sensor A mounted in line with the pulse plate including electronic circuitry (stationary part). Around the circumference of the pulse plate, there are teeth distributed evenly and additional reference markers. This makes it possible to generate an electric pulse pattern when the shaft rotates and the teeth are passing by CMP sensor A. The camshaft position can be determined by counting the number of pulses and deriving the pulse pattern of the electrical signal from CMP sensor A. If the powertrain control module (PCM) recognizes no signal from CMP sensor A, a malfunction is detected and a DTC is stored.

Monitor Execution, Sequence, Duration, DTC Type
Execution
Continuous
Sequence
None
Duration
0.5 second or more
DTC Type
One drive cycle, MIL on

Enable Conditions
Condition
 
State of the engine
Running

Malfunction Threshold
Both conditions occur:
No camshaft signal is detected at least 8 crankshaft revolutions.
The measured input level is less than 1.9 V, or more than 3.2 V.

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 CAM line short to ground
CMP sensor A CAM line short to power
CMP sensor A CAM line open
CMP sensor A failure
PCM internal circuit failure

Confirmation Procedure
Operating Condition
Start the engine, and let it idle.

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.