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Home >> Infiniti >> 2023 >> QX60 Luxe, FWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (1 Of 2) >> System Description >> System >> Automatic Speed Control Device (ASCD) >> System Description
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System Description

SYSTEM DIAGRAM 

GNSDB45530Courtesy of NISSAN
Component parts Function
Brake pedal position switch Stop Lamp Switch Brake Pedal Position Switch 
ASCD steering switch ASCD Steering Switch 
TCM ECM receives the following signals via CAN communication.
  • Output shaft revolution signal
  • Shift position signal
Combination meter
  • ECM receives the vehicle speed signal via CAN communication.
  • ECM transmits ASCD status signal via CAN communication.
ECM ECM (With Barometric Pressure Sensor) 
Electric throttle control actuator Electric Throttle Control Actuator 

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. Operation status of ASCD is indicated by CRUISE indicator and SET indicator in combination meter. If any malfunction occurs in the ASCD system, it automatically deactivates control.

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

SET OPERATION 

Press MAIN switch. (The CRUISE indicator in combination meter illuminates.) When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89 MPH), press COAST/SET switch. (Then SET lamp in combination meter illuminates.)

ACCELERATE OPERATION 

If the ACCEL/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 maintain the new set speed.

CANCEL OPERATION 

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

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

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

COAST OPERATION 

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

RESUME OPERATION 

When the ACCEL/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.