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Inspection Procedure

NOTE: The vehicle is equipped with an SRS (Supplemental Restraint System) which includes components such as airbags. Before servicing (including removal or installation of parts), be sure to read the PRECAUTION in the Supplemental Restraint System (See PRECAUTION ).
  1. INSPECT STEERING PAD SWITCH ASSEMBLY 
    Fig 1: Inspecting Steering Pad Switch Assembly
    G05808023Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the switch 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
      A-9 (AU2) - A-8 (EAU) No switch is pushed 95 to 105 kΩ
      A-9 (AU2) - A-8 (EAU) MODE switch pushed Below 2.5 Ω
      A-9 (AU2) - A-8 (EAU) ON HOOK switch pushed 313.5 to 346.5 Ω
      A-9 (AU2) - A-8 (EAU) OFF HOOK switch pushed 959.5 to 1060.5 Ω
      A-9 (AU2) - A-8 (EAU) VOICE switch pushed 3049.5 to 3370.5 Ω
      A-10 (AU1) - A-8 (EAU) No switch is pushed 95 to 105 kΩ
      A-10 (AU1) - A-8 (EAU) SEEK+ switch pushed Below 2.5 Ω
      A-10 (AU1) - A-8 (EAU) SEEK- switch pushed 313.5 to 346.5 Ω
      A-10 (AU1) - A-8 (EAU) VOL+ switch pushed 959.5 to 1060.5 Ω
      A-10 (AU1) - A-8 (EAU) VOL- switch pushed 3049.5 to 3370.5 Ω

    NG : REPLACE STEERING PAD SWITCH ASSEMBLY 

    OK : Go to next step 

  2. INSPECT SPIRAL CABLE 
    1. Disconnect the cable connectors.
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester connection Spiral Cable Position Specified condition
      K20-4 (EAU) - A-8 (EAU) Center Below 1 Ω
      2.5 rotations to the left
      2.5 rotations to the right
      K20-5 (AU2) - A-9 (AU2) Center Below 1 Ω
      2.5 rotations to the left
      2.5 rotations to the right
      K20-6 (AU1) - A-10 (AU1) Center Below 1 Ω
      2.5 rotations to the left
      2.5 rotations to the right
      NOTE: The spiral cable is an important part of the SRS airbag system. Incorrect removal or installation of the spiral cable may prevent the airbag from deploying. Be sure to read the PRECAUTION for the supplemental restraint system (See PRECAUTION ).

    NG : REPLACE SPIRAL CABLE SUB-ASSEMBLY 

    Fig 2: Identifying Steering Pad Switch Assembly Connector Terminal
    G05808024Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : Go to next step 

  3. CHECK HARNESS AND CONNECTOR (SPIRAL CABLE - RADIO RECEIVER) 
    1. Disconnect the K56 receiver connector.
    2. Disconnect the K20 cable connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      K56-8 (SW2) - K20-5 (AU2) Always Below 1 Ω
      K56-6 (SWG) - K20-4 (EAU) Always Below 1 Ω
      K56-7 (SW1) - K20-6 (AU1) Always Below 1 Ω
      K56-8 (SW2) - Body ground Always 10 kΩ or higher
      K56-6 (SWG) - Body ground Always 10 kΩ or higher
      K56-7 (SW1) - Body ground Always 10 kΩ or higher

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 3: Identifying K56 Receiver Connector And K20 Cable Connector
    G05299843Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : PROCEED TO NEXT INSPECTION PROCEDURE SHOWN IN PROBLEM SYMPTOMS TABLE 

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