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Diagnostic Trouble Code Chart

  1. DOOR ECU 

    Door ECU (driver's side, passenger's side) 

    DIAGNOSTIC TROUBLE CODE DEFINITIONS

    SAE code Item Diagnosis
    B1231  Driver's side jam protection limit switch malfunctions Power window regulator motor assembly LH open in limit switch system
    B1232  Driver's side jam protection sensor malfunctions Power window regulator motor assembly LH open or short in pulse sensor system
    B1233  Passenger's side jam protection limit switch malfunctions Power window regulator motor assembly RH open in limit switch system
    B1234  Passenger's side jam protection sensor malfunctions Power window regulator motor assembly RH open or short in pulse sensor system
  2. TRANSPONDER KEY (IMMOBILISER) ECU 

    Immobilizer ECU 

    DIAGNOSIS CHART

    SAE code Item Diagnosis
    B2780 Key unlock warning switch malfunctions Key unlock warning switch ON is not detected when the ignition switch is ON
  3. MONITOR CODE 
    NOTE:
    • Monitor code shows the switch condition when a DTC is output.
    • In case of that a code is indicated when the switch is not operated, it is detected that the switch is stuck.

      In case of that a code is not indicated when the switch is operated, it is detected that the switch contact condition is bad.

    DIAGNOSIS CHART

    SAE code Item Diagnosis
    B1221 Driver's side switch 1 (operating) Power window switch of master switch or door unlock switch (for manual operation) is ON
    B1223 Passenger's side switch 1 (operating) Switch of the passenger's side regulator switch is ON