Cruise Control System

Description and Operation

Cruise Control

The cruise control system is turned on with the cruise control main switch "ON/OFF" located on the right side of the steering column. The system has cruise, coast, accel, and resume functions.

It also has a safety cancel function that operates when the brake pedal is depressed or the transmission selector lever is shifted.

The ECM is the control module for this system. The main components of the cruise control system are the mode control switches, the transmission range switch, the brake switch, the vehicle speed sensor, the ECM, and the ETC motor, which is connected to the throttle body.

The ECM has a low speed limit that prevents the system from being activated below the minimum speed of 40 km/h.

The controller operation is performed by the mode switches located on the steering wheel.

The transmission range switch and the brake switch are used to cancel the cruise control system. The switches are located on the brake pedal bracket and the transmission. When the brake pedal is depressed or the selector lever is moved, the cruise control system is electrically canceled, and the throttle valve returns to the idle position.

Cruise Control Main Switch (ON/OFF)

The cruise control system is activated by pressing the CRUISE "ON/OFF" main switch. When the CRUISE "ON/OFF" main switch is pressed again, the throttle is reset, cruise is cancelled, the memory speed is erased, and the vehicle is set to non-cruise mode.

SET/– switch

The "SET/–" switch, located on the right side of the steering column, has two functions.

SET function - Press and release the "SET/–" switch at the desired speed. The SET indicator in the instrument cluster will illuminate. Release the accelerator pedal. The desired speed will be maintained automatically.

COAST function - Press and hold the "SET/–" switch while cruise control is on. The vehicle will gradually decelerate. Release the switch at the desired speed. The desired speed will be maintained.

Press the "SET/–" switch and release it quickly. The cruising speed will decrease by 2 km/h.

RES/+ switch

The "RES/+" switch, located on the right side of the steering column, has two functions.

RESUME function - If any method other than the cruise "ON/OFF" main switch was used to temporarily cancel the set speed, and the system is still active, the most recently set speed will automatically resume when the "RES/+" switch is pressed. However, it will not resume if the vehicle speed drops below approximately 40 km/h.

ACCEL function - Press and hold the "RES/+" switch while cruise control is on. The vehicle will gradually accelerate. Release the switch at the desired speed. The desired speed will be maintained.

Press the "RES/+" switch and release it quickly. The cruising speed will increase by 2 km/h.

CANCEL switch

The cruise control system is temporarily canceled by pressing the "CANCEL" switch.

The cruising speed canceled by this switch can be restored by pressing the "RES/+" switch.

Circuit Diagrams

System Block Diagram

Components and Function Description

Component		Function
Vehicle speed sensor, ESP/ABS control module		Converts vehicle speed into a pulse signal.
ECM		Receives signals from sensors and switches.
Cruise Control Indicator		Illuminates when the CRUISE main switch is turned on (built into cluster)
Cruise Control Switches	CRUISE switch	Cruise control power switch.
	RES+ switch	Controls the automatic speed control functions using the Set/Coast switch.
	SET switch
Cancel switches	Cancel switch	Sends cancel signals to the ECM.
	Brake Pedal Switch
	Transmission range switch (A/T)
ETC motor		Controls the throttle valve opening as set by the ECM.

* ETC motor: Electronic Throttle Control motor

Troubleshooting

Symptom Troubleshooting Tables

Symptom Troubleshooting 1

Symptom 2

Symptom of Malfunction	Probable Cause	Remedy
Set vehicle speed fluctuates significantly up or down "Surging" (repeated alternating acceleration and deceleration) occurs after setting the speed.	Vehicle speed sensor circuit malfunction	Repair the vehicle speed sensor system or replace the component.
	Engine control module malfunction	Check the input and output signals at the ECM.

Symptom 3

Symptom of Malfunction	Probable Cause	Remedy
CC system does not cancel when the brake pedal is depressed	Brake switch wiring is damaged or disconnected	Repair the harness or replace the brake pedal switch.
	ECM signal malfunction	Check the input and output signals at the ECM.

Symptom 4

Symptom of Malfunction	Probable Cause	Remedy
CC system does not cancel when the shift lever is moved to the "N" position. (However, it is cancelled when the brake pedal is depressed.)	Inhibitor switch input circuit wiring is damaged or disconnected.	Repair the harness or repair or replace the inhibitor switch.
	Incorrect inhibitor switch adjustment
	ECM signal malfunction	Check the input and output signals at the ECM.

Symptom 5

Symptom of Malfunction	Probable Cause	Remedy
Cannot decelerate (coast) using the "SET/–" switch.	Temporary damage or disconnection of the SET/– switch input circuit wiring	Repair the harness or replace the "SET/–" switch.
	ECM signal malfunction	Check the input and output signals at the ECM.

Symptom 6

Symptom of Malfunction	Probable Cause	Remedy
Cannot accelerate or resume speed using the "RES/+" switch.	Damaged or disconnected wiring, or short circuit, or RES/+ switch input circuit.	Repair the harness or replace the "RES/+" switch.
	ECM signal malfunction	Check the input and output signals at the ECM.

Symptom 7

Symptom of Malfunction	Probable Cause	Remedy
CC system can be set while driving at a speed below 40 km/h (25 mph), or there is no automatic cancellation at this speed.	Vehicle speed sensor circuit malfunction	Repair the vehicle speed sensor system or replace the component.
	ECM signal malfunction	Check the input and output signals at the ECM.

Symptom 8

Symptom of Malfunction	Probable Cause	Remedy
CRUISE CONTROL main switch indicator light does not illuminate (although the CC system operates normally).	Damaged or disconnected cruise control main switch indicator lamp bulb	Repair the harness or replace the component.
	Harness is damaged or disconnected