Cruise Control: Description and Operation

System Outline

The cruise control system is a constant vehicle speed controller which controls the opening angle of the engine throttle valve by the SW, and allows driving at a constant speed without depressing the accelerator pedal.

1. Set Control
When the - SET SW is operated while traveling with the ON-OFF SW on, the speed when the - SET SW is operated to off is memorized, and the vehicle speed is controlled at that speed.

2. Coast Control
When the - SET SW is operated to on, the cruise control opening angle requirement is turned to 0 to decrease the vehicle speed, and the speed when the - SET SW is operated to off is memorized, and the vehicle speed is controlled at that speed.Furthermore, every time the - SET SW is operated momentarily (Approx. 0.5 sec.) to on, the memorized vehicle speed is decreased by approx. 1.5 km/h (0.9 mph).

3. Accel Control
When the + RES SW is operated to on, the throttle motor rotates the throttle valve to open direction to increase the vehicle speed, and the speed when the + RES SW is operated to off is memorized, and the vehicle speed is controlled at that speed.

Furthermore, every time the + RES SW is operated momentarily (Approx. 0.5 sec.) to on, the memorized vehicle speed is increased by approx. 1.5 km/h (0.9 mph).

4. Manual Cancel Mechanism
If any of the following signals are input during cruise control traveling, the current to the motor flows in the direction to close the throttle valve, and cancel the cruise control.
1. Stop light SW is on (Brake pedal is depressed)
2. The CANCEL SW of the control SW is on
3. ON-OFF SW is off
4. Gear is shifted from D position to other positions than D.

5. Resume Control
After canceling the cruise control (except when the ON-OFF SW is off) if the vehicle speed is above the minimum speed limit (Approx. 40 km/h, 25 mph), operating the + RES SW to on from off will cause the system to accelerate and resume to the vehicle speed before manual cancellation.

6. Overdrive Function
The overdrive may be cut on an uphill grade, while traveling with the cruise control.

After the overdrive is cut, if the throttle angle sensor determines that the uphill grade has finished, the overdrive will resume after the overdrive timer operation.

7. Auto Cancel Operation
- If any of the following conditions are detected, the set speed is erased and the control is canceled.
1. Disconnection and/or short in the stop light SW
2. Malfunction in the vehicle speed signal
3. Malfunction in the electronic throttle parts
4. Malfunction in the stop light SW input circuit
5. Malfunction in the cancel circuit
6. The actual vehicle speed becomes -16 km/h slower than the set speed

- If the following condition is detected, the set speed is kept and the control is canceled.
1. The actual vehicle speed becomes slower than the minimum speed limit.