System Description

System Diagram:

SYSTEM DESCRIPTION

1. CRUISE CONTROL SYSTEM
a. Cruise control system makes it possible to drive at a desired speed without using the accelerator pedal. ECM controls the throttle opening angle based on signals from switches and sensors.

The microcomputer which control the cruise control system is built into the ECM, and the actuator is the throttle position sensor and motor.

Constant speed control gets ready when the cruise control main switch ON-OFF button is pushed (the CRUISE main indicator light comes on).

Operating the cruise control main switch, the driver can control the following functions.

HINT:
- The cruise control main switch is an automatic return type switch which turns on only while operating it in each arrow direction and turns off after releasing it.
- 'SET' and '-', 'RES' and '+', 'ON' and 'OFF' operations are share the same switch.

1. 'SET' function
When pushing down the cruise control main switch to "-/SET", the ECM stores the set speed and compares it to actual vehicle speed. If the actual driving speed is greater than the set speed, the ECM sends a signal to the throttle position sensor and motor to close the throttle valve. If lower, it opens the throttle valve. The cruise control operative speed range is between the low and high speed limits.

2. '+' function
A cruise set speed increases while pushing up on the cruise control main switch lever to "+/ RES". The vehicle cruises at the newly set speed when releasing the cruise control main switch lever.

3, Tap-up function
When tapping up on the cruise control main switch lever to "+/RES" (approximately 0.6 second), the ECM increases the stored set speed by 1.6 km/h (1 mph) at a time. However, when the difference between the driving and the stored vehicle speed is more than 5 km/h (approximately 3.1 mph), the stored vehicle speed will not be changed.

4. '-' function
A cruise set speed decreases while pushing down on the cruise control main switch lever to "-/SET". The vehicle cruises at the newly set speed when releasing the cruise control main switch lever.

5. Tap-down function
When tapping down on the cruise control main switch lever to "-/SET" (approximately 0.6 second), the ECM decreases the stored set speed by 1.6 km/h (1 mph) at a time. However, when the difference between the driving and the stored vehicle speed is more than 5 km/h (approximately 3.1 mph), vehicle speed, when the cruise control main switch lever is released from "-/SET", will be stored and constant speed control is maintained.

6. Low speed limit
The lowest possible limit of the speed setting range is approximately 40 km/h (25 mph). The cruise control system cannot be set when the vehicle speed is below the speed limit. Cruise control operation will be automatically canceled and stored vehicle speed will be erased when the vehicle speed goes below the low speed limit while the cruise control is in operation.

7. High speed limit
The highest possible limit of the speed setting range is approximately 200 km/h (125 mph). The cruise control system cannot be set when the vehicle speed is over the high speed limit. Speed up using "+/RES" with the cruise control main switch assembly also cannot be set beyond the high speed limits.

8. 'RES' function
If cruise control operation was canceled under the manual cancel condition (other than turning cruise control main switch ON-OFF button off), 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.

9. MANUAL CANCEL function
The ECM cancels the cruise control under the following conditions while driving:
- The cruise control main switch is pulled to "CANCEL".
- The brake pedal is depressed.
- The clutch pedal is depressed (M/T only).
- The cruise control main switch ON-OFF button is pushed off.

10. AUTO CANCEL function
If any of the following malfunctions occur in the system, the ECM stops the cruising control until the cruise control main switch ON-OFF button is pushed off.
- Stop light switch assembly malfunction
- Vehicle speed signal circuit malfunction
- Throttle body assembly malfunction

If any of the following malfunctions occur to the system, the ECM stops the cruising control until the ignition switch is turned off.
- Stop light switch input circuit malfunction
- CANCEL function circuit malfunction

Under these conditions, the cruise main indicator light blinks until the cruise control main switch ON-OFF button is pushed off.

AUTO CANCEL also works when actual vehicle speed either drops below 40 km/h (25 mph) or is 16 km/h lower than the set speed.