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Inspection Procedure

WARNING: This page is about a different car, the 2004 Toyota Sienna. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT STEERING PAD SWITCH LH (AU1, AU2, EAU) 
    Fig 1: Identifying Steering Pad Switch
    G02934081Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Removing steering pad switch LH.
    2. Check continuity between the terminals at each condition, as shown in the chart.

      Standard: 

      TESTER CONNECTION & SPECIFIC CONDITION

      Tester connection Condition Specified condition
      AU1 - EAU Do not switch position Approx. 100 kΩ
      AU1 - EAU SEEK+ switch: push Approx. 1 Ω
      AU1 - EAU SEEK- switch: push Approx. 0.3 kΩ
      AU1 - EAU VOL+ switch: push Approx. 1 kΩ
      AU1 - EAU VOL- switch: push Approx. 3.2 kΩ
      AU2 - EAU Do not switch position Approx. 100 kΩ
      AU2 - EAU MODE switch: push Approx. 1 Ω
    1. NG: REPLACE STEERING PAD SWITCH LH (See  REPLACEMENT  ) 
    2. OK: Go to next step. 
  2. CHECK HARNESS AND CONNECTOR (STEERING PAD SWITCH LH - RADIO RECEIVER ASSY) 
    Fig 2: Identifying Steering Pad Switch C13 & Radio Receiver Assy R13
    G02934082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the connector from the steering pad switch LH and radio receiver assy.
      1. Check continuity between the terminals at each condition, as shown in the chart.

        Standard: 

        TESTER CONNECTION & SPECIFIC CONDITION

        Tester connection Specified condition
        SW1 - AU1 Continuity
        SW2 - AU2 Continuity
        GND - EAU Continuity
      2. Check for a short between the terminals at each condition, as shown in the chart.

        Standard: 

        TESTER CONNECTION & SPECIFIC CONDITION

        Tester connection Specified condition
        SW1 - Body ground No continuity
        SW2 - Body ground No continuity
        GND - Body ground No continuity
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: REPLACE RADIO RECEIVER ASSY (See  REPLACEMENT  )