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Home >> Lexus >> 2012 >> IS 250C Standard Trans >> 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: the constant speed control mode and vehicle-to-vehicle distance control mode.

    • The vehicle-to-vehicle distance control mode is always selected when starting up the dynamic radar cruise control system.
    • Operation of the constant speed control mode is the same as that for a conventional cruise control system.
    1. Inspect the SET function.
      Fig 1: Identifying ON-OFF And -SET Switches
      GTY277243Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 ON-OFF
      *2 -SET
      1. Turn the cruise control on using the main switch.
      2. Drive at the required speed (50 km/h (30 mph) or higher).
      3. Push the cruise control main switch to -SET.
      4. After releasing the switch, check that the vehicle cruises at the set speed.
    2. Inspect the + (ACCEL) function.
      Fig 2: Identifying ON-OFF And +RES Switches
      GTY268288Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 ON-OFF
      *2 +RES
      1. Turn the cruise control on using the main switch.
      2. Drive at the required speed (50 km/h (30 mph) or higher).
      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 5 km/h (5 mph)

    3. Inspect the - (COAST) function.
      Fig 3: Identifying ON-OFF And -SET Switches
      GTY277243Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 ON-OFF
      *2 -SET
      1. Turn the cruise control on using the main switch.
      2. Drive at the required speed (50 km/h (30 mph) or higher).
      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 5 km/h (5 mph).

    4. Inspect the CANCEL function.
      Fig 4: Identifying ON-OFF And CANCEL Switches
      GTY261985Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 ON-OFF
      *2 CANCEL
      1. Turn the cruise control on using the main switch.
      2. Drive at the required speed (50 km/h (30 mph) or higher).
      3. Push the cruise control main switch to -SET.
      4. When performing any one of the following, check that cruise control operation is canceled and that the normal driving mode returns.
        • Depressing the brake pedal
        • Moving the shift lever from D or S to the others
        • Selecting 3rd, 2nd or 1st range with the shift lever in S
        • Selecting 3rd, 2nd or 1st range with the shift paddle switch
        • Pulling the cruise control main switch to CANCEL
        • Turning the cruise control main switch off
    5. Inspect the RES (RESUME) function.
      Fig 5: Identifying ON-OFF And +RES Switches
      GTY268288Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 ON-OFF
      *2 +RES
      1. Turn the cruise control on using the main switch.
      2. Drive at the required speed (50 km/h (30 mph) or higher).
      3. Push the cruise control main switch to -SET.
      4. Cancel cruise control operation 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 speed of more than 40 km/h (25 mph), check that the vehicle resumes the speed set prior to the cancellation.

        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.