Infiniti G37 Coupe. Manual - part 472

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

EC-69

< FUNCTION DIAGNOSIS >

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C

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 : Vehicle front

1.

Power steering pressure sensor

2.

Alternator

3.

Engine oil temperature sensor

 : Vehicle front

1.

EVAP service port

2.

EVAP canister purge volume control 
solenoid valve

3.

EVAP canister

4.

EVAP canister vent control valve

5.

EVAP control system pressure sen-
sor

 : Vehicle front

1.

Fuel level sensor unit and fuel pump 
harness connector

2.

Fuel level sensor unit and fuel pump 3.

Fuel pressure regulator

4.

Fuel tank temperature sensor

1.

Accelerator pedal position sensor

2.

ECM

JMBIA0845ZZ

JMBIA0019ZZ

JMBIA0015ZZ

EC-70

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AUTOMATIC SPEED CONTROL DEVICE (ASCD)

Component Description

INFOID:0000000001733946

1.

ICC steering switch

2.

CANCEL switch

3.

RESUME/ACCELERATE switch

4.

SET/COAST switch

5.

DISTANCE switch

6.

MAIN switch

1.

ASCD steering switch

2.

CANCEL switch

3.

RESUME/ACCELERATE switch

4.

SET/COAST switch

5.

MAIN switch

1.

Stop lamp switch

2.

ASCD brake switch (ASCD models)
ICC brake switch (ICC models)

3.

Brake pedal

4.

ASCD clutch switch (ASCD models)
ICC clutch switch (ICC models)

5.

Clutch pedal

JMBIA0016ZZ

JMBIA0017ZZ

JMBIA0051ZZ

Component

Reference

ASCD steering switch

EC-421, "Description"

ASCD brake switch

EC-428, "Description"

Stop lamp switch

EC-428, "Description"

Electric throttle control actuator

EC-404, "Description"

ASCD indicator

EC-480, "Description"

CAN COMMUNICATION

EC-71

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CAN COMMUNICATION

System Description

INFOID:0000000001733947

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-8, "CAN Communication Control Circuit"

, about CAN communication for detail..

EC-72

< FUNCTION DIAGNOSIS >

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COOLING FAN CONTROL

COOLING FAN CONTROL

System Diagram

INFOID:0000000001733948

System Description

INFOID:0000000001733949

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

ECM controls cooling fan speed corresponding to vehicle speed, engine coolant temperature, air conditioner
ON signal, refrigerant pressure, target A/C evaporator temperature and A/C evaporator temperature.
Cooling fan control signal is sent to IPDM E/R from ECM by CAN communication line. Then, IPDM E/R sends
ON/OFF pulse duty signal to cooling fan control module. Corresponding to this ON/OFF pulse duty signal,
cooling fan control module gives cooling fan motor operating voltage to cooling fan motors. Cooling fan speed
is controlled by duty cycle of cooling fan motor operating voltage sent from cooling fan control module.

JMBIA0075GB

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 control module

↓

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.

Vehicle speed*

2

Air conditioner ON signal*

2

A/C evaporator temperature*

2

Target A/C evaporator temperature*

2