System Description

The cruise control system maintains constant vehicle speed. It enables the driver to adjust the vehicle speed by operating the cruise control main switch without using the accelerator pedal.

The hybrid vehicle control ECU receivers signals from each switch and sensor, and maintains constant vehicle speed by optimizing the use of the engine and motor driving force.

• The hybrid vehicle control ECU receives signals such as ON-OFF, - SET, + RES, and CANCEL from the cruise control main switch and executes the command.
• The hybrid vehicle control ECU illuminates the combination meter's cruise main indicator light when it receives a cruise control main switch (ON-OFF button) ON signal.
  Fig 1: Identifying Cruise Main Indicator Light "SET" Indicator

  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  TEXT IN ILLUSTRATION
  
  

  *1	Cruise Main Indicator Light
  *2	"SET" Indicator

• The hybrid vehicle control ECU displays "SET" on the combination meter when constant speed control is started by pushing the cruise control main switch to "- SET".
• The hybrid vehicle control ECU cancels cruise control operation when the brake pedal is depressed and the hybrid vehicle control ECU receives a stop light switch signal.
• The hybrid vehicle control ECU cancels cruise control operation when the shift lever is moved from D to N or B, and the hybrid vehicle control ECU receives a shift position sensor signal.

1. Low speed limit

   The lowest possible limit of the speed setting range is set at approximately 40 km/h (25 mph). The cruise control system cannot be set when the vehicle speed is below the low speed limit. Cruise control operation will be automatically canceled but the stored vehicle speed will be retained when the vehicle speed drops below the low speed limit of 40 km/h (25 mph) while the cruise control is operating.

2. High speed limit

   The highest possible limit of the speed setting range is set at approximately 200 km/h (125 mph). The cruise control system cannot be set when the vehicle speed is over this limit. Also, + RES cannot be used to increase speed over this limit.

The cruise control main switch operates 7 functions: SET, -, TAP-DOWN, RES, +, TAP-UP, and CANCEL. The SET, TAP-DOWN, and - functions, and the RES, TAP-UP, and + functions are operated with the same switch. The cruise control main switch is an automatic return type switch which turns on only while it is being operated in the direction of each arrow and turns off after being released.

1. SET CONTROL
   Fig 2: Identifying Cruise Main Indicator Light "SET" Indicator Multi Information Display

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Vehicle speed is stored and constant speed control is maintained when pushing the cruise control main switch to - SET while driving with the main switch on (the cruise main indicator light and "SET" indicator come on), and the vehicle speed is within the set speed range (between the low and high speed limits).

   TEXT IN ILLUSTRATION
   
   

   *1	Cruise Main Indicator Light
   *2	"SET" Indicator
   *3	Multi Information Display

2. - CONTROL

   The hybrid vehicle control ECU decreases the cruise control demand speed and controls the engine and motor driving force to decelerate the vehicle when - SET on the cruise control main switch is pressed and held while the cruise control system is operating. When the cruise control main switch is released from - SET, vehicle speed is stored and constant speed control is maintained.

3. TAP-DOWN CONTROL

   When tapping down the cruise control main switch to - SET (for approximately 0.6 seconds) while the cruise control system is operating, the stored vehicle speed decreases each time by approximately 1.6 km/h (1 mph). When the cruise control main switch is released from - SET and the difference between the driving and stored vehicle speeds is more than 5 km/h (3 mph), the vehicle speed is stored and constant speed control is maintained.

4. + CONTROL

   The hybrid vehicle control ECU increases the cruise control demand speed and controls the engine and motor driving force to accelerate the vehicle when pushing and holding the cruise control main switch to + RES while the cruise control system is operating.

   When the cruise control main switch is released from + RES, vehicle speed is stored and constant speed control is maintained.

5. TAP-UP CONTROL

   When tapping up the cruise control main switch to + RES (for approximately 0.6 seconds) while the cruise control system is operating, the stored vehicle speed increases each time by approximately 1.6 km/h (1 mph). However, when the difference between the driving and the stored vehicle speeds is more than 5 km/h (3 mph), the stored vehicle speed will not be changed.

6. RES CONTROL

   If cruise control operation was canceled with the stop light switch assembly or the CANCEL switch, and if driving speed is within the limit range, pushing the cruise control main switch to + RES restores vehicle speed memorized at the time of cancellation, and maintains constant speed control.

7. MANUAL CANCEL CONTROL

   Performing any of the following cancels the cruise control system while it is operating (the stored vehicle speed in the hybrid vehicle control ECU is maintained).

   • Depressing the brake pedal
   • Moving the shift lever from D to N or B
   • Pushing the cruise control main switch to CANCEL
   • Turning the cruise control main switch (ON-OFF button) off (the stored vehicle speed in the hybrid vehicle control ECU is not maintained)

This system has an automatic cancellation function (fail-safe). Refer to FAIL-SAFE TABLE .