Infiniti G37 Coupe. Manual - part 69

AV

U1000 CAN COMM CIRCUIT

AV-29

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COMPONENT DIAGNOSIS

U1000 CAN COMM CIRCUIT

Description

INFOID:0000000001684419

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 independently). In CAN communication, control units are connected with 2
communication lines (CAN-H, CAN-L) allowing a high rate of information transmission with less wiring. Each
control unit transmits/receives data but selectively reads required data only.
CAN Communication Signal Chart. Refer to 

LAN-25, "CAN System Specification Chart"

.

DTC Logic

INFOID:0000000001684420

DTC DETECTION LOGIC

Diagnosis Procedure

INFOID:0000000001684421

1.

PERFORM SELF-DIAGNOSTIC

1.

Turn ignition switch ON and wait for 2 seconds or more.

2.

Check “Self Diagnostic Result” of “MULTI AV”. 

Is “CAN COMM CIRCUIT” displayed?

YES

>> Refer to “LAN system”. Refer to 

LAN-16, "Trouble Diagnosis Flow Chart"

.

NO

>> Refer to GI section. Refer to 

GI-38, "Intermittent Incident"

.

DTC

Display contents of CON-

SULT-III

Diagnostic item is detected when ...

Probable malfunction location

U1000

CAN COMM CIRCUIT

AV control unit is not transmitting or receiving 
CAN communication signal for 2 seconds or 
more.

CAN communication system.

AV-30

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U1010 CONTROL UNIT (CAN)

U1010 CONTROL UNIT (CAN)

Description

INFOID:0000000001684422

Initial diagnosis of AV control unit.

DTC Logic

INFOID:0000000001684423

DTC DETECTION LOGIC

Diagnosis Procedure

INFOID:0000000001684424

1.

REPLACE AV CONTROL UNIT

When DTC U1010 is detected, replace AV control unit.

>> INSPECTION END

DTC

Display contents of CON-

SULT-III

Diagnostic item is detected when ...

Probable malfunction location

U1010

CONTROL UNIT (CAN)

CAN initial diagnosis malfunction is detected.

AV control unit.

AV

U1310 AV CONTROL UNIT

AV-31

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U1310 AV CONTROL UNIT

Description

INFOID:0000000001684425

Replace the AV control unit if this DTC is displayed. Refer to 

AV-109, "Exploded View"

.

DTC Logic

INFOID:0000000001684426

Part name

Description

AV CONTROL UNIT

• It is the master unit of the MULTI AV system, and it is connected to each control 

unit by communication. It operates each system according to communication 
signals from the AV control unit.

• AV control unit includes audio function and vehicle information function.
• It is connected to ECM and unified meter and A/C amp via CAN communica-

tion to obtain necessary information for the vehicle information function.

• It is connected to BCM via CAN communication transmitting/receiving for the 

vehicle settings function.

• It inputs the illumination signals that are required for the display dimming con-

trol.

• It inputs the signals for driving status recognition (vehicle speed, reverse and 

parking brake). 

• Auxiliary image signal is input from the auxiliary input jacks.

DTC

Display contents of 

CONSULT-III

DTC Detection Condition

Action to take

U1310

CONTROL UNIT (AV)
[U1310]

An initial diagnosis error is detected in AV communication 
circuit.

Replace AV control unit.

AV-32

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U1200 AV CONTROL UNIT

U1200 AV CONTROL UNIT

Description

INFOID:0000000001684427

Replace the AV control unit if this DTC is displayed. Refer to 

AV-109, "Exploded View"

.

DTC Logic

INFOID:0000000001684428

Part name

Description

AV CONTROL UNIT

• It is the master unit of the MULTI AV system, and it is connected to each control 

unit by communication. It operates each system according to communication 
signals from the AV control unit.

• AV control unit includes audio function and vehicle information function.
• It is connected to ECM and unified meter and A/C amp via CAN communica-

tion to obtain necessary information for the vehicle information function.

• It is connected to BCM via CAN communication transmitting/receiving for the 

vehicle settings function.

• It inputs the illumination signals that are required for the display dimming con-

trol.

• It inputs the signals for driving status recognition (vehicle speed, reverse and 

parking brake). 

• Auxiliary image signal is input from the auxiliary input jacks.

DTC

Display contents of 

CONSULT-III

DTC Detection Condition

Action to take

U1200

Cont Unit
FLASH- ROM
[U1200]

An internal malfunction is detected in AV control unit 
(FLASH-ROM).

Replace AV control unit.