System Description
Caution: Do not use the cruise control on slippery roads, steeply graded roads,
or in heavy traffic of heavy or varying volume. Failure to follow these CAUTIONS
could possibly cause you to loose control of the vehicle and result in damage
to the vehicle and personal injury.
The computer which controls the cruise control system is combined with the powertrain control module (PCM), and the actuator uses the throttle position sensor and motor. A microcomputer is built into the PCM to control ON-OFF, SET/COAST, RESUME/ACCEL,
CANCEL, vehicle speed operation, motor output control and overdrive control functions.
The PCM compares the driving vehicle speed from the speed sensor with the stored vehicle speed set through the cruise control main switch assembly. The PCM instructs the throttle valve motor of the throttle position sensor and motor to close the valve
when the driving vehicle speed is grater than the stored vehicle speed, and instructs it to open the valve when the driving speed is greater than the stored vehicle speed, and instructs it to open the valve when the driving speed is less than the stored speed.
The PCM receives signals such as ON-OFF, SET/COAST, RESUME/ACCEL and CANCEL from the cruise control main switch assembly and executes them.
The PCM turns on the indicator in the instrument panel based upon the ON signal from the cruise control main switch assembly.
The PCM cancels the cruise control system when it detects that the brake pedal is depressed, based on the stop lamp switch signal.
The PCM cancels the cruise control system when it detects that the shift position is changed from D to any position except D, based on the park/neutral position switch assembly signal.
Limit Control
| • | 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 driving vehicle speed is below the low speed limit. Cruise control
operation will be automatically canceled and the stored vehicle speed will be erased when the vehicle speed goes below the low speed limit while the cruise control is in operation. |
| • | 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 driving vehicle speed is over the high speed limit. Speed up
using RES/ACC (RESUME/ACCELERATION) with the cruise control main switch assembly also cannot be set beyond the high speed limit. |
System Operation
The cruise control main switch operates the SET, COAST, TAP-DOWN, RESUME, ACCEL, TAP-UP and CANCEL functions. The SET, TAP-DOWN and COAST functions, and the RESUME, TAP-UP and ACCEL functions are operated with the same switch. The
cruise control main switch assembly is an automatic return type switch which turns on only while operating it in each arrow direction and turns off after releasing it.
| • | SET CONTROL - Vehicle speed is stored and constant speed control is maintained when the switch is released from SET/COAST wile driving with the cruise control main switch ON-OFF button on (the CRUISE main indicator light is On), and the
vehicle speed is within the set speed range (between the low and high speed limits). |
| • | COAST CONTROL - The PCM makes the cruise control demanding throttle opening angle zero degrees and decelerates the vehicle (the throttle valve is not fully closed due to idle speed control, etc.) when SET/COAST on the cruise control main switch
is pressed and held while the cruise control system is in operation. Vehicle speed, when the cruise control main switch is released from SET/COAST, is stored and constant speed control is maintained. |
| • | TAP-DOWN CONTROL - When tapping down on the cruise control main switch to SET/COAST (for approximately 0.5 second) while the cruise control system is in operation, the stored vehicle speed decreases each time by approximately 1.6 km/h
(1.0 mph). However, when the difference between the driving and the stored vehicle speed is more than 5 km/h (3.1 mph), the vehicle speed, when the cruise control main switch is released from SET/COAST, will be stored and constant speed
control is maintained. |
| • | ACCELERATION CONTROL - The throttle valve motor of the throttle position sensor and motor is instructed by the PCM to open the valve when RES/ACC on the cruise control main switch is pressed and held while the cruise control system is in operation.
Vehicle speed, when the cruise control main switch is released from RES/ACC, is stored and the vehicle is controlled at a constant speed. |
| • | TAP-UP CONTROL - When tapping up on the cruise control main switch to RES/ACC (for approximately 0.5 second) while the cruise control system is in operation, the stored vehicle speed increases each time by approximately 1.6 km/h
(1.0 mph). However when the difference between the driving and the stored vehicle speed is more than 5 km/h (3.1 mph), the stored vehicle speed will not be changed. |
| • | RESUME CONTROL - If cruise control operation was cancelled with the stop lamp switch or the CANCEL switch, and if driving speed is within the limit range, pushing the cruise control main switch to RES/ACC restores vehicle speed memorized at
the time of cancellation, and maintains constant speed control. |
| • | MANUAL CANCEL CONTROL - Doing any of the following cancels the cruise control system while in operation (the stored vehicle speed in the PCM is maintained): |
| • | Depressing the brake pedal |
| • | Depressing the clutch pedal (Manual transaxle) |
| • | Moving the shift lever to any position except D (Automatic transaxle) |
| • | Pushing the cruise control main switch to CANCEL |
| • | Pushing the cruise control main switch ON-OFF button Off (The stored vehicle speed in the PCM is not maintained.) |
| • | OTHER CANCEL CONTROL - Cruise control will be halted if VSC starts operation while driving (Vehicle speed will be memorized.) |
AUTO CANCEL (FAIL-SAFE)
If the following conditions are detected while the cruise control is in operation, the system clears the stored vehicle speed in the PCM and cancels the cruise control operation.
| • | The CRUISE main indicator light blinks. |
| • | An open or short in the stop lamp switch circuit. |
| • | A problem with the vehicle speed signal. |
| • | A problem with the throttle position sensor and motor. |
| • | A problem with the input circuit of the stop lamp switch circuit. |
| • | A problem with the cancel circuit. |
| • | The CRUISE main indicator light goes off. |
| • | Vehicle speed is lower than the low speed limit, approximately 40 km/h (25 mph) while running with the cruise control On. |
| • | Vehicle speed is lower than the stored speed by approximately 16 km/h (9.9 mph) or more. |
