DTC P064D [L3]: Notes

2010 Mazda 5 Sport, 2.3 L, StandardSECTION Notes
WARNING: This page is about a different car, the 2008 Mazda 5. However, it is still accessible from the selected car via links, so may be relevant.
DTC P064D [L3] DETECTION CONDITIONS AND POSSIBLE CAUSES

DTC P064D Internal control module front HO2S processor performance
DETECTION CONDITION 
  • The front HO2S IC integrated in PCM converts to voltage value for fuel control and for diagnosis based on the front HO2S signal current and sends to CPU (integrated in PCM). The CPU switches the voltage value for the fuel control and for the diagnosis in the fuel control once during one drive cycle, and compares the voltage values. If the difference of compared value is below threshold, the PCM determines that the signal circuit between CPU and front HO2S control IC has malfunction.

MONITORING CONDITIONS 
  • HO2S heater, HO2S, and TWC verification drive mode
  • Following conditions are met
    • Engine is running or ignition switch is ON position
    • All front HO2S (PCM terminals 2Z, 2AD, 2AC) signal voltage is 1.2V - battery voltage-1.2 V

Diagnostic support note 
  • This is a continuous monitor (HO2S).
  • The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycle or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
  • PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA is available.
  • DTC is stored in PCM memory.
POSSIBLE CAUSE 
  • PCM internal malfunction (between CPU and front HO2S control IC communication line)
RENDER: 1.0x

NO RELATED

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