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Home >> Mazda >> 2021 >> 3 Select, 4D Hatchback, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (VINS 7, L, M) (1 Of 4) >> DTC P0137-00: Ho2S Circuit Low Input >> Details On DTCs
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Details On DTCs

DTC P0137:00 (PCM, VINs 7, L, M, US) DETECTION CONDITION AND POSSIBLE CAUSE

Description HO2S circuit low input
Detection condition Determination conditions
  • A condition in which the HO2S input voltage is less than the specified value continues for the specified period.
Preconditions
  • HO2S is activated.
  • The following DTCs are not detected:
  • MAF sensor: P0100:00, P0101:00 and U060F:00
    • ECT sensor No. 1: P0117:00 and P0118:00
Malfunction determination period
  • 5 s period
Drive cycle
  • 2
Self test type
  • CMDTC self test
Sensor used
  • HO2S
Fail-safe function
  • Fixes duty value of A/F sensor heater
  • Stops fuel feedback control of A/F sensor
Vehicle status when DTCs are output
  • Not applicable
Possible cause
  • HO2S connector or terminals malfunction
  • PCM connector or terminals malfunction
  • Short to ground in HO2S signal (+) circuit
  • Open circuit in any of the following HO2S circuits.
  • Signal (+) circuit
    • Signal (-) circuit
  • HO2S malfunction
  • PCM malfunction
G13712084Courtesy of MAZDA MOTORS CORP.