System Description

SYSTEM DIAGRAM

Courtesy of NISSAN NORTH AMERICA, INC.

Component parts	Function
Stop lamp switch	Stop Lamp Switch .
BCM	ECM transmits the brake operation signal via CAN communication.
ASCD steering switch	ASCD Steering Switch .
TCM	ECM receives the output shaft revolution signal via CAN communication.
ABS actuator and electric unit (control unit)	ECM receives the vehicle speed signal via CAN communication.
ECM	ECM .
Electric throttle control actuator	Electric Throttle Control Actuator .
Combination meter	It transmits the ASCD status signal to combination meter via CAN communication.

BASIC ASCD SYSTEM

Refer to Owner's Manual for ASCD operating instructions, Automatic Speed Control Device (ASCD) allows a driver to keep vehicle at predetermined constant speed without depressing accelerator pedal. Driver can set vehicle speed in advance between approximately 40 km/h (25 MPH) and 144 km/h (89 MPH). ECM controls throttle angle of electric throttle control actuator to regulate engine speed. The ASCD operation status is indicated by two indicators (CRUISE and SET on the information display) on the combination meter. If any malfunction occurs in ASCD system, SET indicator blinks and ASCD control is deactivated.

NOTE: Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.

SET OPERATION

Press MAIN switch. (CRUISE is indicated on the information display). When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89 MPH), press SET- switch or RES+ switch. (Then SET is indicated on the information display.)

NOTE: If press RES+ switch when there is no set speed, the set speed is set to the current speed.

ACCELERATE OPERATION

If the RES+ switch is pressed during cruise control driving, increase the vehicle speed until the switch is released or vehicle speed reaches maximum speed controlled by the system, And then ASCD will keep the new set speed.

CANCEL OPERATION

When any of following conditions exist, cruise operation will be canceled.

CANCEL switch is pressed
More than 2 switches at ASCD steering switch are pressed at the same time (Set speed will be cleared)
Brake pedal is depressed
Selector lever is changed to N, P, R position
Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed
TCS system is operated

When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform the driver by blinking indicators.

Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE indicator may blink slowly. When the engine coolant temperature decreases to the normal operating temperature, CRUISE indicator will stop blinking and the cruise operation will be able to work by pressing SET- switch or RES+ switch.
Malfunction for some self-diagnoses regarding ASCD control: SET indicator will blink quickly.

If MAIN switch is turned to OFF during ASCD is activated, all of ASCD operations will be canceled and vehicle speed memory will be erased.

COAST OPERATION

When the SET- switch is pressed during cruise control driving, decrease vehicle set speed until the switch is released. And then ASCD will keep the new set speed.

RESUME OPERATION

When the RES+ switch is pressed after cancel operation other than pressing MAIN switch is performed, vehicle speed will return to last set speed. To resume vehicle set speed, vehicle condition must meet following conditions.

Brake pedal is released
Selector lever is in other than P and N positions
Vehicle speed is greater than 40 km/h (25 MPH) and less than 144 km/h (89 MPH)