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Home >> Mazda >> 2009 >> 5 Touring, 2.3 L >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System L3] >> DTC P2128 [L3] >> Notes
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DTC P2128 [L3]: Notes

DTC P2128 (L3) DETECTION CONDITION & POSSIBLE CAUSES

DTC P2128 Accelerator pedal position (APP) sensor No.2 circuit high input
DETECTION CONDITION 
  • The PCM monitors the input voltage from APP sensor No.2 when the engine is running. If the input voltage is above 7.2 V for 1s, the PCM determines that the APP sensor No.2 circuit has malfunction.

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • APP sensor connector or terminal malfunction
  • Short to power supply in wiring harness between APP sensor terminal E and PCM terminal 1 AO
  • APP sensor No.2 malfunction
  • PCM connector or terminal malfunction
  • Open circuit in wiring harness between APP sensor terminal D and body ground
  • Open circuit in wiring harness between APP sensor terminal E and PCM terminal 1 AO
  • Open circuit in wiring harness between APP sensor terminal F and main relay
  • PCM malfunction
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