Nissan Teana J32. Manual - part 380

EC-58

< FUNCTION DIAGNOSIS >

[VQ25DE, VQ35DE]

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

Component Description

INFOID:0000000003856480

1.

Fuel level sensor unit and fuel pump 
harness connector

2.

Fuel pressure regulator

3.

Fuel level sensor unit and fuel pump

: Vehicle front

JMBIA1385ZZ

Component

Reference

ASCD steering switch

EC-270, "Description"

ASCD brake switch

EC-273, "Description"

ASCD clutch switch

EC-273, "Description"

Stop lamp switch

EC-291, "Description"

Electric throttle control actuator

EC-302, "Description"

ASCD indicator

EC-323, "Description"

CAN COMMUNICATION

EC-59

< FUNCTION DIAGNOSIS >

[VQ25DE, VQ35DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

CAN COMMUNICATION

System Description

INFOID:0000000003856481

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-22, "CAN System Specification Chart"

, about CAN communication for detail.

EC-60

< FUNCTION DIAGNOSIS >

[VQ25DE, VQ35DE]

COOLING FAN CONTROL

COOLING FAN CONTROL

System Diagram

INFOID:0000000003856482

System Description

INFOID:0000000003856483

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 through 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].

JMBIA1324GB

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

Battery

Battery voltage*

1

ABS actuator and electric unit (control unit)

Vehicle speed*

2

Engine coolant temperature sensor

Engine coolant temperature

BCM

Air conditioner ON signal*

2

Refrigerant pressure sensor

Refrigerant pressure

COOLING FAN CONTROL

EC-61

< FUNCTION DIAGNOSIS >

[VQ25DE, VQ35DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

Cooling Fan Operation

Cooling Fan Relay Operation

The ECM controls cooling fan relays in the IPDM E/R through 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