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Inspection Procedure

  1. CHECK HARNESS AND CONNECTOR (MAYDAY ECU - MAP LIGHT (MAYDAY SWITCH)) 
    1. Disconnect the R23 ECU connector.
    2. Disconnect the X4 map light connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      R23-13 (SIG2) - X4-31 (SIG2) Always Below 1 Ω
      R23-12 (SIG-) - X4-32 (GND3) Always Below 1 Ω
      Fig 1: Identifying R23 ECU And X4 Map Light Connector Terminals
      G04945812Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR THEN CLEAR HISTORIC DTC 

      OK: Go to Next Step 

  2. INSPECT MAP LIGHT ASSEMBLY (MAYDAY SWITCH) 
    1. Remove the map light for standard body (see REMOVAL ) or long body (see REMOVAL ).
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      31 (SIG2) - 32 (GND3) SERVICES button is pressed 305 to 313 Ω
      31 (SIG2) - 32 (GND3) PHONE button is pressed 812 to 831 Ω
      31 (SIG2) - 32 (GND3) PTT button is pressed 1811 to 1848 Ω
      Fig 2: Identifying Map Light Assembly Connector Terminal
      G04945809Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPLACE MAP LIGHT ASSEMBLY (MAYDAY SWITCH) THEN CLEAR HISTORIC DTC 

      OK: REPLACE MAYDAY ECU TOGETHER WITH MAYDAY BATTERY AND THEN PERFORM REGISTRATION