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Inspection Procedure

WARNING: This page is about a different car, the 2008 Scion xB. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT FUSE (HTR-IG) 
    1. Remove the HTR-IG fuse from the main body ECU.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester Connection Condition Specified condition
      HTR-IG fuse Always Below 1 Ω

    NG : REPLACE FUSE  (See PARTS LOCATION  )

    OK: Go to Next Step 

  2. INSPECT NO. 3 HEATER CONTROL 
    1. Measure the resistance.
      1. Remove the No. 3 heater control.
      2. Measure the resistance according to the value(s) in the table below.

        Standard resistance 

        TESTER CONNECTION AND SPECIFIED CONDITION

        Tester Connection Switch Condition Specified Condition
        C20-2 (B) - C20-3 (A/C) Heater control base (A/C): LOCK Below 1 Ω
        C20-2 (B) - C20-3 (A/C) Heater control base (A/C): FREE 10 kΩ or higher
        Fig 1: Identifying No. 3 Heater Control Connector Terminals
        G05389930Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check that the indicator light comes on.
      1. Connect the positive (+) lead from the battery to terminal 3 and negative (-) to terminal 4, and check that the indicator light comes on.

        OK: The indicator light comes on. 

    3. Reinstall the No. 3 heater control.

    NG : REPLACE NO. 3 HEATER CONTROL  (See DISASSEMBLY  )

    OK: Go to Next Step 

  3. CHECK HARNESS AND CONNECTOR (NO. 3 HEATER CONTROL - BATTERY) 
    1. Disconnect the C20 No. 3 heater control connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester Connection Switch Condition Specified condition
      C20-2 (B) -Body ground Ignition switch ON 11 to 14 V
      C20-2 (B) - Body ground Ignition switch OFF Below 1 V
      Fig 2: Identifying C20 No. 3 Heater Control Connector Terminals
      G05389931Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reconnect the No. 3 heater control connector.

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  4. CHECK HARNESS AND CONNECTOR (NO. 3 HEATER CONTROL - A/C AMPLIFIER) 
    1. Disconnect the C20 No. 3 heater control connector.
    2. Disconnect the C8 A/C amplifier connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester connection Condition Specified condition
      C20-3 (A/C) - C8-15 (A/C) Always Below 1 Ω
      C20-4 (AIND) - C8-16 (LED) Always Below 1 Ω
      C20-3 (A/C) - Body ground Always 10 kΩ or higher
      C20-4 (AIND) - Body ground Always 10 kΩ or higher
      Fig 3: Identifying C8 A/C Amplifier And C20 No. 3 Heater Control Connector Terminals
      G00461783Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Reconnect the No. 3 heater control connector.
    5. Reconnect the A/C amplifier connector.

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK : PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE   .

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