1. GENERAL
HINT:
2. FUNCTION OF MAIN COMPONENTS
Item |
Outline |
Combination Meter (CRUISE Main Indicator Light) |
|
Combination Meter (Master Warning Light) | If the ECM or distance control ECU detects an automatic cancel signal while the vehicle is operating under cruise control, this light comes on to inform the driver |
Combination Meter (Buzzer) | If the ECM or distance control ECU detects an automatic cancel signal while the vehicle is operating under cruise control, this buzzer sounds only once to inform the driver |
Combination Meter (Multi-information Display) |
|
Cruise Control Main Switch (Main Switch) | Turns the cruise control system ON/OFF |
Cruise Control Main Switch (Control Switch) |
|
Steering Pad Switch (Distance Control Switch) | While the system is in the vehicle-to-vehicle distance control mode, the driver can operate the steering pad switch (distance control switch) to select the vehicle-to-vehicle distance in three stages: long, middle, and short |
Stop Light Switch | Detects the depression of the brake pedal and transmits its signal to the ECM |
Combination Switch (Wiper Switch) | Transmits wiper control switch information to the distance control ECU |
Laser Sensor | Radiates laser rays forward, uses the reflected rays for detecting the presence of a vehicle in front, vehicle-to-vehicle distance, and relative speed, and transmits this information to the distance control ECU |
Steering Angle Sensor | Detects the angle and direction of steering and transmits its signal to the distance control ECU |
Vehicle Speed Sensor (SP1) | A vehicle speed signal which is output from the skid control ECU is sent to the ECM via the meter |
Yaw Rate Sensor | Detects the yaw rate of the vehicle and transmits its signal to the distance control ECU |
Brake Actuator (Skid Control ECU) |
|
Skid Control Buzzer | This buzzer sounds upon receiving a signal from the skid control ECU |
ECM |
|
Throttle Position Sensor and Motor | Upon receiving a signal from the ECM, the throttle control motor actuates the throttle valve |
Distance Control ECU | While the system is in the vehicle-to-vehicle distance control mode, the distance control ECU detects a vehicle in front based on a signal from the laser sensor. Then, the distance control ECU calculates the acceleration or deceleration rate in order to attain the target vehicle-tovehicle distance, and outputs a request signal to the ECM and skid control ECU. |
3. LIMIT CONTROL
4. CRUISE CONTROL OPERATION
The cruise control main switch operates 8 functions: SET, - (COAST), TAP-DOWN, RES (RESUME), + (ACCEL), TAP-UP, CANCEL, and MODE. The SET, TAP-DOWN, and - (COAST) functions, and the RES (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 the direction of each arrow and turns off after releasing it. The dynamic laser cruise control system has two cruise control modes: the constant speed control mode and vehicle-to-vehicle distance control mode.
HINT: An actual throttle valve opening angle of 0 is not possible due to the idle speed control, etc.
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.
5. BRAKE CONTROL
The distance control ECU determines the distance to the vehicle in front, relative speed, target decreasing speed, and deceleration rate. Based on these data, the ECU transmits a brake demand signal to the skid control ECU via the ECM.
6. DOWN SHIFT CONTROL
While the cruise control system is in operation, the transmission may downshift from an overdrive gear on an uphill road. After the downshift, if the system determines that the uphill inclination has become smaller based on the throttle valve opening angle, the transmission automatically returns to an overdrive gear.
7. AUTO CANCEL (FAIL-SAFE)
How to proceed with
troubleshooting
HINT:
Use the following procedures to troubleshoot the cruise
control system.
*: Use the intelligent tester.
1 VEHICLE BROUGHT TO WORKSHOP
2 PROBLEM SYMPTOM CONFIRMATION
3 CHECK MULTIPLEX COMMUNICATION SYSTEM*
Refer to HOW TO PROCEED WITH TROUBLESHOOTING.
Check fo ...
Removal
1. REMOVE V-BANK COVER SUB-ASSEMBLY (See
page EM-28)
2. DISCONNECT VENTILATION HOSE
(a) Disconnect the ventilation hose from the ventilation
valve.
3. REMOVE VENTILATION VALVE
(a) Remove the ventilation valve. ...
Blower Motor Circuit
DESCRIPTION
The blower motor is operated by signals from the A/C amplifier. Blower motor
speed signals are
transmitted by changes in the Duty Ratio.
Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle. For
example, if A is the period of
continuity in one cycl ...