DTC P0340 [LF]: Notes

DTC P0340 (LF) DETECTION CONDITION AND POSSIBLE CAUSE

DTC P0340	CMP sensor circuit problem
DETECTION CONDITION	The PCM monitors the input voltage from the CMP sensor when the engine is running. If the PCM does not receive the input voltage from the CMP sensor while the PCM receives the input signal from the CKP sensor, the PCM determines that the CMP sensor circuit has a malfunction. If a malfunction is detected in the input pulse pattern from the CMP sensor. Diagnostic support note This is a continuous monitor (CCM). The MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle. FREEZE FRAME DATA (Mode 2/Mode 12) is available. The DTC is stored in the PCM memory.
POSSIBLE CAUSE	CMP sensor connector or terminals malfunction Short to ground in wiring harness between CMP sensor terminal C and PCM terminal 2AM Short to ground in wiring harness between CMP sensor terminal B and PCM terminal 2S PCM connector or terminals malfunction Short to power supply in wiring harness between CMP sensor terminal B and PCM terminal 2S CMP sensor circuits are shorted to each other Open circuit in wiring harness between CMP sensor terminal C and PCM terminal 2AM Open circuit in wiring harness between CMP sensor terminal B and PCM terminal 2S Open circuit in wiring harness between CMP sensor terminal A and PCM terminal 2P CMP sensor malfunction CMP sensor pulse wheel malfunction CMP sensor looseness Valve timing mechanism misinstallation Timing chain misinstallation Loose camshaft sprocket lock bolt Loose crankshaft pulley lock bolt Loose timing chain or improper valve timing PCM malfunction
Courtesy of MAZDA MOTORS CORP.

DTC P0340

CMP sensor circuit problem

DETECTION CONDITION

The PCM monitors the input voltage from the CMP sensor when the engine is running. If the PCM does not receive the input voltage from the CMP sensor while the PCM receives the input signal from the CKP sensor, the PCM determines that the CMP sensor circuit has a malfunction.
If a malfunction is detected in the input pulse pattern from the CMP sensor.

Diagnostic support note

This is a continuous monitor (CCM).
The MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle.
FREEZE FRAME DATA (Mode 2/Mode 12) is available.
The DTC is stored in the PCM memory.

POSSIBLE CAUSE

CMP sensor connector or terminals malfunction
Short to ground in wiring harness between CMP sensor terminal C and PCM terminal 2AM
Short to ground in wiring harness between CMP sensor terminal B and PCM terminal 2S
PCM connector or terminals malfunction
Short to power supply in wiring harness between CMP sensor terminal B and PCM terminal 2S
CMP sensor circuits are shorted to each other
Open circuit in wiring harness between CMP sensor terminal C and PCM terminal 2AM
Open circuit in wiring harness between CMP sensor terminal B and PCM terminal 2S
Open circuit in wiring harness between CMP sensor terminal A and PCM terminal 2P
CMP sensor malfunction
- CMP sensor pulse wheel malfunction
CMP sensor looseness
Valve timing mechanism misinstallation
- Timing chain misinstallation
- Loose camshaft sprocket lock bolt
- Loose crankshaft pulley lock bolt
Loose timing chain or improper valve timing
PCM malfunction

Courtesy of MAZDA MOTORS CORP.