DTC P0340: Notes

2008 Mazda 6 s Sport, 4D Hatchback, StandardSECTION Notes
WARNING: This page is about a different car, the 2007 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
DTC P0340 DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0340 Camshaft position (CMP) sensor circuit malfunction
DETECTION CONDITION 
  • PCM monitors the input voltage from the CMP sensor when 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 circuit has a malfunction.

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • MIL illuminates if the PCM detects the above malfunction condition during first drive cycle.
  • FREEZE FRAME DATA is available.
  • DTCs are stored in the PCM memory.
POSSIBLE CAUSE 
  • CMP sensor malfunction
  • Connector or terminal malfunction
  • CMP sensor is dirty
  • Short to the power circuit between CMP sensor terminal C and PCM terminal 2E
  • Short to the power circuit between CMP sensor terminal B and PCM terminal 2H
  • Short to ground circuit between CMP sensor terminal A and main relay
  • Short to ground circuit between CMP sensor terminal C and PCM terminal 2E
  • Open circuit between CMP sensor terminal A and main relay
  • Open circuit between CMP sensor terminal B and PCM terminal 2H
  • Open circuit between CMP sensor terminal C and PCM terminal 2E
  • Both CMP sensor wires are shorted to each other
  • CKP sensor pulse wheel malfunction
  • CKP sensor misinstallation
  • Timing chain misinstallation
  • Loose timing chain or improper valve timing
  • Loose camshaft sprocket lock bolt
  • Loose crankshaft pulley lock bolt
  • PCM malfunction
G04324122Courtesy of MAZDA MOTORS CORP.
RENDER: 1.0x

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