System Outline

The cruise control system is a constant vehicle speed controller in which the opening of the engine throttle valve is adjusted automatically and can be controlled by hand without the driver needing to depress the accelerator pedal.

Constant Speed Control
When the actual vehicle speed is faster than the set vehicle speed, a signal is sent to the electric throttle motor to rotate it in order to close the throttle valve. Alternatively, when the vehicle speed is slower than the set vehicle speed, a signal is sent to the electric throttle motor to rotate it in order to open the throttle valve.
Setting
When the operating the - SET SW with the ON-OFF SW turned ON (Within the settable rage of the vehicle speed: Above the low speed limit and below the high speed limit), the vehicle speed at which the SW is released is stored in the memory and the vehicle is controlled to drive at that speed constantly.
Coast, Tap Down
< Coast >

If the - SET SW is held ON while driving with the cruise control active, the coast control makes the cruise control request opening equal 'Zero' (Note: the throttle valve is not completely closed due to idle speed control, etc.) to decelerate the vehicle and stores the vehicle speed in the memory at the point which the SW is released and controls the vehicle to drive constantly at that speed.

< Tap down >

If the - SET SW is pressed ON momentarily (Approx. 0.6 sec.), the set vehicle speed is decelerated in an approximately 1.6 km/h (1 mph) step for each SW press. If the tap down operation puts more than 5 km/h (3 mph) difference between the set vehicle speed and actual vehicle speed, the vehicle speed at which the SW is released is stored in the memory and the vehicle is controlled to drive constantly at that speed.
Acceleration, Tap Up
< Acceleration >

If the + RES SW is held ON while driving with the cruise control active, the acceleration control rotates the electric throttle motor to open the throttle valve to accelerate the vehicle slowly and constantly. The vehicle speed at which the SW is released is stored in the memory and the vehicle is controlled to drive constantly at that speed.

< Tap Up >

If the + RES SW is pressed ON momentarily (Approx. 0.6 sec.), the set vehicle speed is accelerated in an approximately 1.6 km/h (1 mph) steps for each SW press. When the difference between the set vehicle speed and actual vehicle speed is more than 5 km/h (3 mph), the tap up operation does not change the set vehicle speed.
Low Speed Limit
The low speed limit is the minimum speed that the cruise control can be set at and is set at approximately 40 km/h (25 mph). The cruise control cannot be set if the vehicle speed is slower than the low speed limit. When the vehicle speed drops below the low speed limit while driving with the cruise control active, the cruise control will be cancelled but the set speed will be retained.
High Speed Limit
The high speed limit is the maximum speed that the cruise control can be set at and is set to be approximately 200 km/h (125 mph). The cruise control cannot be set if the vehicle speed is faster than the high speed limit. The vehicle cannot be accelerated above the high speed limit with the + RES SW operation.
Cancel
When the following signals are received while driving with the cruise control active, the cruiser control will be cancelled.
1. Stop lamp SW ON
2. CANCEL SW ON from the control SW
3. ON-OFF SW OFF
4. D position circuit ON to OFF from the park/neutral position SW (Shift position is shifted from D or 4 to N, 3, 2 or L) (A/T)
5. Cruise control clutch SW OFF (Clutch pedal depressed) (M/T)
Resume
If the vehicle speed stays higher than the low speed limit after the cruise control has been canceled by one of the above signals (Except (3) ON-OFF SW OFF), the cruise control can be made to resume operation and return the vehicle to the speed that was set at the time the driver canceled the cruise control by pressing the + RES SW ON momentarily.
Downshift Control
While driving with the cruise control active, the A/T may force the transmission to downshift if a steep hill is encountered. If a downshift has occurred, then the A/T will upshift the transmission again soon after the hill climbing has finished. This will be determined by the throttle valve opening signals. However, if the downshift occurred during acceleration control or resume control, the upshift will take place after the control ends.
Auto Cancel
1. The set vehicle speed will be erased from memory and the cruise control will be cancelled in the situations outlined below. Until the ON-OFF SW is turned ON again, the cruise operation indicator blinks and the cruise control can not be activated.
  * When the stop lamp SW has been disconnected or short-circuited.
  
  * When the vehicle speed signal is abnormal.
  
  * When the electronic throttle parts are abnormal.
2. The set vehicle speed will be erased from memory and the cruise control will be cancelled in the situations outlined below. Until the ON-OFF SW is turned ON again, the cruise operation indicator blinks and the cruise control can not be activated until the ignition SW has been turned OFF and then ON again.
  * When the stop lamp SW input circuit is abnormal.
  
  * When the cancel circuit is abnormal.
3. The set vehicle speed will be erased from memory and the cruise control will be cancelled in the situation outlined below. When the vehicle speed drops below the set speed minus 16 km/h (10 mph). (Set speed erased)
4. The cruise control will be cancelled in the situation outlined below.
  * When the vehicle speed falls below than the low speed limit. (Set speed retained)