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Inspection Procedure

  1. READ VALUE OF INTELLIGENT TESTER 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the engine switch on (IG) and turn the intelligent tester main switch on.
    3. Check the DATA LIST for proper functioning of the cruise control main switch.
    Fig 1: Checking Functioning Of Cruise Control Main Switch
    G05298713Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    ECM (Cruise control): 

    DIAGNOSTIC NOTE CHART

    Item Measurement Item / Display (Range) Normal Condition Diagnostic Note
    MAIN SW (MAIN) Main switch signal (Main CPU) / ON or OFF ON: Main switch ON (Pushed on)
    OFF: Main switch OFF (Pushed off)
    -
    CANCEL SW CANCEL switch signal / ON or OFF ON: CANCEL switch ON
    OFF: CANCEL switch OFF
    -
    SET/COAST SW SET/COAST switch signal / ON or OFF ON: SET / COAST switch ON
    OFF: SET / COAST switch OFF
    -
    RES/ACC SW RES/ACC switch signal / ON or OFF ON: RES/ACC switch ON
    OFF: RES / ACC switch OFF
    -

    OK: 

    When cruise control main switch operation is performed, the result will be same as above. 

    Result: 

    RESULT CHART

    Result Proceed to
    OK A
    NG (all items are defective) B
    NG (1 to 3 items are defective) C

    A: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

    C: REPLACE CRUISE CONTROL MAIN SWITCH 

    B: Go to next step 

  2. INSPECT CRUISE CONTROL MAIN SWITCH 
    1. Disconnect the cruise control main switch connector.
      Fig 2: Inspecting Cruise Control Main Switch
      G05298714Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. 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
      1 - 2, 1 - 3 Neutral 10 kΩ or higher
      1 - 3 RES/ACC 235 to 245 Ω
      1 - 3 SET/COAST 620 to 640 Ω
      1 - 3 CANCEL 1510 to 1570 Ω
      1 - 3 Main Switch OFF 10 kΩ or higher
      1 - 3 Main Switch ON Below 1 Ω
      1 - 2 MODE Below 1 Ω

    NG: REPLACE CRUISE CONTROL MAIN SWITCH 

    OK: Go to next step 

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

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Condition Specified Condition
      A-1 - K20-7 Below 1 Ω
      A-3 - K20-1 Below 1 Ω
      A-4 - K20-2 Below 1 Ω
    Fig 3: Checking Spiral Cable
    G05298639Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SPIRAL CABLE 

    OK: Go to next step 

  4. CHECK WIRE HARNESS (SPIRAL CABLE - ECM) 
    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
      K20-1 - A7-31 (CCS) Always Below 1 Ω
      K20-7 - A6-20 (CCHG) Always Below 1 Ω
      K20-1 - Body ground Always 10 kΩ or higher
      K20-7 - Body ground Always 10 kΩ or higher
    Fig 4: Checking Wire Harness (Spiral Cable - ECM)
    G05298716Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS AND CONNECTOR 

    OK: Go to next step 

  5. CHECK WIRE HARNESS (SPIRAL CABLE - 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
      K20-2 - Body ground Always Below 1 Ω
    Fig 5: Identifying K20 Connector Terminals
    G05298717Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS AND CONNECTOR 

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