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Home >> Lexus >> 2012 >> HS 250h >> Repair and Diagnosis >> Accessories & Equipment >> Cruise Control Systems >> Dynamic Radar Cruise Control System (Diagnostics - Introduction) >> Dynamic Radar Cruise Control System >> Road Test >> Road Test
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Road Test

  1. PROBLEM SYMPTOM CONFIRMATION 

    HINT: 

    The dynamic radar cruise control system has two cruise control modes: constant speed control mode and vehicle-to-vehicle distance control mode.

    • Vehicle-to-vehicle distance control mode is always selected when starting up the dynamic radar cruise control system.
    • Operation of constant speed control mode is the same as that for a conventional cruise control system.
    1. Inspect the SET function.
      TEXT IN ILLUSTRATION

      *1 ON/OFF
      *2 - SET
      Fig 1: Inspecting SET Function
      GTY228325Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Turn the cruise control on using the main switch.
      2. Check that the cruise main indicator light illuminates on the combination meter assembly.
      3. Drive at a speed between 50 km/h (30 mph) and 170 km/h (105 mph).
      4. Push the cruise control main switch to - SET.
        TEXT IN ILLUSTRATION

        *1 Cruise Main Indicator Light
        *2 "SET" Indicator
        Fig 2: Identifying "SET" On The Combination Meter
        GTY270990Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Check that "SET" is indicated on the combination meter.
      6. After releasing the switch, check that the vehicle cruises at the set speed.
    2. Inspect the + (ACCEL) function.
      TEXT IN ILLUSTRATION

      *1 ON/OFF
      *2 - SET
      *3 + RES
      Fig 3: Inspecting RES (RESUME) Function
      GTY227667Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Turn the cruise control on using the main switch.
      2. Drive at a speed between 50 km/h (30 mph) and 170 km/h (105 mph).
      3. Push the cruise control main switch to - SET.
      4. Check that vehicle speed increases while the cruise control main switch is pushed to + RES, and that the vehicle cruises at the newly set speed when the switch is released.
      5. Push the cruise control main switch to + RES and then release it immediately. Check that vehicle speed increases* (tap-up control).

        HINT: 

        *: Constant speed control mode: increases by 1.6 km/h (1.0 mph); vehicle-to-vehicle distance control mode: increases by 1 km/h or 1 mph.

    3. Inspect the - (COAST) function.
      TEXT IN ILLUSTRATION

      *1 ON/OFF
      *2 - SET
      Fig 4: Inspecting SET Function
      GTY228325Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Turn the cruise control on using the main switch.
      2. Drive at a speed between 50 km/h (30 mph) and 170 km/h (105 mph).
      3. Push the cruise control main switch to - SET.
      4. Check that vehicle speed decreases while the cruise control main switch is pushed to - SET, and the vehicle cruises at the newly set speed when the switch is released.
      5. Push the cruise control main switch to - SET, and then release it immediately. Check that vehicle speed decreases* (tap-down control).

        HINT: 

        *: Constant speed control mode: decreases by 1.6 km/h (1.0 mph); vehicle-to-vehicle distance control mode: decreases by 1.6 km/h or 1 mph.

    4. Inspect the CANCEL function.
      TEXT IN ILLUSTRATION

      *1 ON/OFF
      *2 - SET
      *3 CANCEL
      Fig 5: Inspecting CANCEL Function
      GTY235108Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Turn the cruise control on using the main switch.
      2. Drive at a speed between 50 km/h (30 mph) and 170 km/h (105 mph).
      3. Push the cruise control main switch to - SET.
      4. When performing any one of the following, check that the cruise control system is canceled and that the normal driving mode is reset.
        • Depressing the brake pedal
        • Moving the shift lever from D to N or D to B
        • Turning the main switch off
        • Pulling the cruise control main switch to CANCEL
    5. Inspect the RES (RESUME) function.
      TEXT IN ILLUSTRATION

      *1 ON/OFF
      *2 - SET
      *3 + RES
      Fig 6: Inspecting RES (RESUME) Function
      GTY227667Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Turn the cruise control on using the main switch.
      2. Drive at a speed between 50 km/h (30 mph) and 170 km/h (105 mph).
      3. Push the cruise control main switch to - SET.
      4. Cancel the cruise control system by performing any of the above operations (other than turning the main switch off).
      5. After pushing the cruise control main switch to "+ RES" at a driving speed of more than 40 km/h (25 mph), check that the vehicle resumes the speed set prior to the cancellation and that "SET" is also displayed on the combination meter.

        HINT: 

        The stored vehicle speed is retained even if vehicle speed drops below 40 km/h (25 mph) once. The previously stored vehicle speed can be resumed by pushing the cruise control main switch to + RES when vehicle speed returns to approximately 40 km/h (25 mph) or more.