2009 Scion xB AutomaticFACTORY OEM SERVICE PROCEDURE

Inspection Procedure

  1. INSPECT FUSES (DEF, ECU-IG NO. 2, HTR-IG) 
    1. Remove the DEF, ECU-IG NO. 2 and HTR-IG fuses from the main body ECU.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TERMINALS RESISTANCE REFERENCE

      Item Condition Specified Condition
      DEF fuse Always Below 1 Ω
      ECU-IG NO. 2 fuse Always Below 1 Ω
      HTR-IG fuse Always Below 1 Ω
    3. Reinstall the fuses.

    NG : REPLACE FUSES 

    Fig 1: Identifying DEF, ECU-IG No. 2 And HTR-IG Fuses
    G05391335Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (REAR WINDOW DEFOGGER WIRE BATTERY POSITIVE) 
    1. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      L1-1 - Body ground Ignition switch ON Rear defogger switch ON 11 to 14 V

    NG:  Go to step  4

    Fig 2: Identifying Rear Window Defogger Wire Connector Terminals
    G05391336Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (REAR WINDOW DEFOGGER WIRE CONNECTOR BODY GROUND) 
    1. Disconnect the L2 rear window defogger wire connector.
    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
      L2-1 - Body ground Always Below 1 Ω
    3. Reconnect the rear window defogger wire connector.

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 3: Identifying L2 Rear Window Defogger Wire Connector Terminals
    G05391337Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : REPAIR OR REPLACE REAR WINDOW DEFOGGER WIRE  (See REPAIR  )

  4. CHECK HARNESS AND CONNECTOR (REAR WINDOW DEFOGGER WIRE - MAIN BODY ECU) 
    1. Disconnect the 2F main body ECU connector.
    2. Disconnect the L1 rear window defogger wire 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
      L1-1 - 2F-2 Always Below 1 Ω
      L1-1 - Body ground Always 10 kΩ or higher
    4. Reconnect the main body ECU connector.
    5. Reconnect the rear window defogger wire connector.

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 4: Identifying L1 Rear Window Defogger Wire Connector Terminals
    G05391338Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (REAR WINDOW DEFOGGER SYSTEM POWER SOURCE) 
    1. Disconnect the 2G main body ECU connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      2G-1 - Body ground Ignition switch ON 11 to 14 V
    3. Reconnect the main body ECU connector.

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 5: Identifying 2G Main Body ECU Connector Terminals
    G05391339Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  6. INSPECT MAIN BODY ECU (DEF RELAY) 
    Fig 6: Identifying Main Body ECU (DEF Relay) Connector Terminals
    G05391340Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the main body ECU.
    2. Remove the ECU-IG NO. 2 fuse from the main body ECU.
    3. Measure the resistance of the DEF relay.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      2G-1 - 2F-2 When battery voltage absent 10 kΩ or higher
      2G-1 - 2F-2 When battery voltage applied to terminals 2Ω - 12 and ECU-IG NO. 2 fuse (DEF relay side) Below 1 Ω
    4. Reinstall the fuse.
    5. Reinstall the main body ECU.

    NG : REPLACE MAIN BODY ECU 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (HEATER CONTROL (REAR DEFOGGER SWITCH) MAIN BODY ECU) 
    1. Disconnect the C40 heater control connector.
    2. Disconnect the 2Q main body ECU 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
      C40-2 (RDEF) - 2Q-12 Always Below 1 Ω
      C40-3 (IG+) - 2Q-10 Always Below 1 Ω
      C40-2 (RDEF) - Body ground Always 10 kΩ or higher
      C40-3 (IG+) - Body ground Always 10 kΩ or higher
    4. Reconnect the heater control connector.
    5. Reconnect the main body ECU connector.

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 7: Identifying C40 Heater Control Connector Terminals
    G05391341Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (HEATER CONTROL - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      C40-5 (E) - Body ground Always Below 1 Ω

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 8: Identifying C40 Heater Control Connector Terminals
    G05391342Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : REPLACE HEATER CONTROL  (See DISASSEMBLY )

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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