Nissan Altima L32. Manual - part 494

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

EC-1097

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Component Description

INFOID:0000000004361980

1.

ASCD brake switch

2.

Stop lamp switch

3.

Brake pedal 

4.

ASCD steering switch

5.

ASCD clutch switch (M/T models)

6.

Clutch pedal

ALBIA0105ZZ

Component

Reference

ASCD brake switch

EC-1413, "Description"

ASCD clutch switch

EC-1413, "Description"

ASCD indicator

EC-1472, "Description"

ASCD steering switch

EC-1410, "Description"

Electric throttle control actuator

EC-1446, "Description"

Park/neutral position (PNP) switch (M/T)

EC-1382, "Description"

Stop lamp switch

EC-1434, "Description"

TCM (CVT)

EC-1382, "Description"

EC-1098

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[VQ35DE]

CAN COMMUNICATION

CAN COMMUNICATION

System Description

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CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-

tiplex communication line with high data communication speed and excellent error detection ability. Many elec-

tronic control units are equipped onto a vehicle, and each control unit shares information and links with other

control units during operation (not independent). In CAN communication, control units are connected with 2

communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.

Each control unit transmits/receives data but selectively reads required data only.

Refer to 

LAN-25, "CAN Communication Signal Chart"

, about CAN communication for detail.

COOLING FAN CONTROL

EC-1099

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COOLING FAN CONTROL

System Diagram

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System Description

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INPUT/OUTPUT SIGNAL CHART

*1: The ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to ECM via the CAN communication line.

SYSTEM DESCRIPTION

The ECM controls the cooling fan corresponding to the vehicle speed, engine coolant temperature, refrigerant

pressure, and air conditioner ON signal. The control system has 4-step control [HIGH/MIDDLE/LOW/OFF].

JMBIA1969GB

Sensor

Input signal to ECM

ECM function

Actuator

Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)

Engine speed*

1

Cooling fan 
control

IPDM E/R
↓
Cooling fan relay
↓
Cooling fan motor

Engine coolant temperature sensor

Engine coolant temperature

Refrigerant pressure sensor

Refrigerant pressure

Battery

Battery voltage*

1

Unified meter and A/C amp.

Air conditioner ON signal*

2

Vehicle speed*

2

EC-1100

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[VQ35DE]

COOLING FAN CONTROL

Cooling Fan Operation

Cooling Fan Relay Operation

The ECM controls cooling fan relays in the IPDM E/R via the CAN communication line.

JMBIA0179GB

Cooling fan speed

Cooling fan relay

1

2

3

Stop (OFF)

OFF

OFF

OFF

Low (LOW)

ON

OFF

OFF

Middle (MID)

OFF

ON

OFF

High (HI)

OFF

ON

ON