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Home >> Lexus >> 2012 >> IS F >> Repair and Diagnosis >> Accessories & Equipment >> Cruise Control Systems >> Dynamic Radar Cruise Control System (Diagnostics & Circuit Tests) >> Dynamic Radar Cruise Control System >> Circuit Tests >> Cruise Control Switch Circuit >> Procedure
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Cruise Control Switch Circuit: Procedure

  1. READ VALUE USING TECHSTREAM 
    Fig 1: Identifying Cruise Control Main Switch Operating Direction
    GTY150862Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Radar Cruise / Data List.
    5. Check the Data List for proper functioning of the cruise control main switch.
      RADAR CRUISE (ECM)

      Techstream Display Measurement Item/Range Normal Condition Diagnostic Note
      Main SW M-CPU Main switch signal (Main CPU) / ON or OFF ON: Main switch on
      OFF: Main switch off      		 -
      Cancel Switch CANCEL switch signal / ON or OFF ON: CANCEL switch on
      OFF: CANCEL switch off      		 -
      SET/COAST Switch - (COAST)/SET switch signal / ON or OFF ON: - (COAST)/SET switch on
      OFF: - (COAST)/SET switch off      		 -
      RES/ACC Switch + (ACCEL)/RES switch signal / ON or OFF ON: + (ACCEL)/RES (RESUME) switch on
      OFF: + (ACCEL)/RES (RESUME) switch off      		 -

      OK

      When the cruise control main switch is operated, the display changes as shown above.

      Result

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

    B → See step   2 

    C → See step   8 

    A → See step   7 

  2. INSPECT CRUISE CONTROL MAIN SWITCH 
    1. Remove the cruise control main switch. Refer to REMOVAL .
      Fig 2: Measuring Cruise Control Main Switch
      GTY136812Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      A-1 (ECC) - A-2 (R/N)
      A-1 (ECC) - A-3 (CCS)      		 Main Switch off 1 MΩ or higher
      A-1 (ECC) - A-3 (CCS) Main switch on Below 2.5 Ω
      A-1 (ECC) - A-2 (R/N) MODE Below 2.5 Ω
      A-1 (ECC) - A-3 (CCS) + RES 235 to 245 Ω
      A-1 (ECC) - A-3 (CCS) - SET 617 to 643 Ω
      A-1 (ECC) - A-3 (CCS) CANCEL 1509 to 1571 Ω
    3. Reinstall the cruise control main switch. Refer to INSTALLATION .

    NG → See step   8 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (SPIRAL CABLE - CRUISE CONTROL MAIN SWITCH) 
    1. Disconnect the spiral cable connector.
      Fig 3: M1 Connector
      GTY140835Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A-1 (ECC) - m1-4 (ECC) Always Below 1 Ω
      A-2 (R/N) - m1-1 (R/N) Always Below 1 Ω
      A-3 (CCS) - m1-3 (CCS) Always Below 1 Ω
    3. Reconnect the spiral cable connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. INSPECT SPIRAL CABLE 
    NOTE:

    The spiral cable is an important part of the SRS airbag system. Incorrect removal or installation of the spiral cable may cause airbag deployment. Be sure to read information shown in the brackets.

    HINT: 

    1. Remove the spiral cable. Refer to COMPONENTS .
      Fig 4: Identifying Terminals Of Spiral Cable Connector
      GTY152991Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      m1-1 (R/N) - J24-7 (R/N) The spiral cable position is center Below 1 Ω
      The spiral cable position is 2.5 rotations to the left
      The spiral cable position is 2.5 rotations to the right
      m1-3 (CCS) - J24-1 (CCS) The spiral cable position is center Below 1 Ω
      The spiral cable position is 2.5 rotations to the left
      The spiral cable position is 2.5 rotations to the right
      m1-4 (ECC) - J24-2 (ECC) The spiral cable position is center Below 1 Ω
      The spiral cable position is 2.5 rotations to the left
      The spiral cable position is 2.5 rotations to the right

      HINT: 

      The spiral cable makes a maximum of approximately 5 rotations.

    NG → See step   9 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (SPIRAL CABLE - ECM, BODY GROUND) 
    1. Disconnect the ECM connectors.
      Fig 5: Identifying Terminals Of A5 And A6 Connectors
      GTY123977Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      J24-1 (CCS) - A6-15 (CCS) Always Below 1 Ω
      J24-7 (R/N) - A5-17 (CCHG) Always Below 1 Ω
      J24-1 (CCS) - Body ground Always 10 kΩ or higher
      J24-7 (R/N) - Body ground Always 10 kΩ or higher
      J24-2 (ECC) - Body ground Always Below 1 Ω
    3. Reconnect the ECM connectors.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   6 

  6. REPLACE ECM (for 2UR-GSE). Refer to  COMPONENTS 
  7. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE 
  8. REPLACE CRUISE CONTROL MAIN SWITCH. Refer to  COMPONENTS 
  9. REPLACE SPIRAL CABLE. Refer to  COMPONENTS 
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