Infiniti FX35, FX50 (S51). Manual - part 266

U1000, U1002 CAN COMM CIRCUIT

BRC-95

< DTC/CIRCUIT DIAGNOSIS >

[VDC/TCS/ABS]

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U1000, U1002 CAN COMM CIRCUIT

Description

INFOID:0000000005234610

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.

DTC Logic

INFOID:0000000005234611

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

DTC REPRODUCTION PROCEDURE

1.

Turn the ignition switch ON.

2.

Perform self-diagnosis for “ABS” with CONSULT-III.

Is DTC “U1000” or “U1002” detected?

YES

>> Proceed to diagnosis procedure. Refer to 

BRC-95, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000005234612

1.

PERFORM ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)

Perform self-diagnosis for “ABS” with CONSULT-III.

Is DTC “U1000” or “U1002” detected?

YES

>> Proceed to diagnosis procedure. Refer to 

LAN-20, "Trouble Diagnosis Flow Chart"

.

NO

>> INSPECTION END

Special Repair Requirement

INFOID:0000000005528352

1.

ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION

Always perform the neutral position adjustment for the steering angle sensor, when replacing the ABS actua-
tor and electric unit (control unit). Refer to 

BRC-9, "ADJUSTMENT OF STEERING ANGLE SENSOR NEU-

TRAL POSITION : Description"

.

>> END

DTC

Display item

Malfunction detected condition

Possible cause

U1000

CAN COMM CIRCUIT

When ABS actuator and electric unit (control unit) is not 
transmitting or receiving CAN communication signal for 2 
seconds or more.

• CAN communication line
• ABS actuator and electric unit 

(control unit)

U1002

SYSTEM COMM

When ABS actuator and electric unit (control unit) is not 
transmitting or receiving CAN communication signal for 2 
seconds or less.

BRC-96

< DTC/CIRCUIT DIAGNOSIS >

[VDC/TCS/ABS]

U1100 CAN COMM CIRCUIT (ICC UNIT)

U1100 CAN COMM CIRCUIT (ICC UNIT)

Description

INFOID:0000000005234614

The ABS actuator and electric unit (control unit) and the ICC sensor integrated unit exchange signals via the
CAN communication line.

DTC Logic

INFOID:0000000005234615

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

DTC REPRODUCTION PROCEDURE

1.

Turn the ignition switch ON.

2.

Perform self-diagnosis for “ABS” with CONSULT-III.

Is DTC “U1100” detected?

YES

>> Proceed to diagnosis procedure. Refer to 

BRC-96, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000005234616

1.

CHECK CAN COMMUNICATION LINE

Check CAN communication line. Refer to 

BRC-95, "Diagnosis Procedure"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace error-detected parts.

2.

CHECK ICC INTEGRATED UNIT

Perform self-diagnosis for “ICC” with CONSULT-III.

Is the inspection result normal?

YES

>> ABS actuator and electric unit (control unit).

NO

>> Repair or replace error-detected parts.

Special Repair Requirement

INFOID:0000000005528353

1.

ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION

Always perform the neutral position adjustment for the steering angle sensor, when replacing the ABS actua-
tor and electric unit (control unit). Refer to 

BRC-9, "ADJUSTMENT OF STEERING ANGLE SENSOR NEU-

TRAL POSITION : Description"

.

>> END

DTC

Display item

Malfunction detected condition

Possible cause

U1100

ACC COMM CIRCUIT

When there is a malfunction in the CAN communication 
circuit or ICC sensor integrated unit.

• CAN communication line
• ABS actuator and electric unit 

(control unit)

• ICC integrated unit

POWER SUPPLY AND GROUND CIRCUIT

BRC-97

< DTC/CIRCUIT DIAGNOSIS >

[VDC/TCS/ABS]

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POWER SUPPLY AND GROUND CIRCUIT

Description

INFOID:0000000005234618

Supplies power to ABS actuator and electric unit (control unit).

Diagnosis Procedure

INFOID:0000000005234619

1.

CHECK ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) IGNITION POWER SUPPLY

1.

Turn the ignition switch OFF.

2.

Disconnect ABS actuator and electric unit (control unit) harness connector.

3.

Check the voltage between ABS actuator and electric unit (control unit) harness connector and ground.

4.

Turn the ignition switch ON.

CAUTION:

Never start the engine.

5.

Check the voltage between ABS actuator and electric unit (control unit) harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 2.

2.

CHECK ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) IGNITION POWER SUPPLY CIRCUIT

1.

Turn the ignition switch OFF.

2.

Check 10 A fusible link (45).

3.

Disconnect IPDM E/R harness connector.

4.

Check continuity between ABS actuator and electric unit (control unit) harness connector and IPDM E/R
harness connector.

Is the inspection result normal?

YES

>> Perform the trouble diagnosis for ignition power supply circuit. Refer to 

PG-81, "Wiring Diagram -

IGNITION POWER SUPPLY -"

.

NO

>> Repair or replace error-detected parts.

3.

CHECK ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) POWER SUPPLY

1.

Turn the ignition switch OFF.

2.

Check the voltage between ABS actuator and electric unit (control unit) harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 4.

ABS actuator and electric unit (control unit)

—

Condition

Voltage

Connector

Terminal

E41

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Ground

Ignition switch: OFF

Approx. 0 V

ABS actuator and electric unit (control unit)

—

Condition

Voltage 

Connector

Terminal

E41

28

Ground

Ignition switch: ON

Battery voltage

ABS actuator and electric unit (control unit)

IPDM E/R

Continuity

Connector

Terminal

Connector

Terminal

E41

28

E5

25

Existed

ABS actuator and electric unit (control unit)

—

Voltage

Connector

Terminal

E41

2

Ground

Battery voltage

3

BRC-98

< DTC/CIRCUIT DIAGNOSIS >

[VDC/TCS/ABS]

POWER SUPPLY AND GROUND CIRCUIT

NO

>> Perform the trouble diagnosis for power supply circuit.

4.

CHECK ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) GROUND

Check the continuity between ABS actuator and electric unit (control unit) harness connector and ground.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Repair or replace error-detected parts.

ABS actuator and electric unit (control unit)

—

Continuity

Connector

Terminal

E41

1

Ground

Existed

4