Infiniti G35 (V35) Sedan. Manual - part 1299

STC-86

< COMPONENT DIAGNOSIS >

[WITH 4WAS]

U1010 4WAS COMMUNICATION CIRCUIT

U1010 4WAS COMMUNICATION CIRCUIT

Description

INFOID:0000000000958822

• 4WAS front control unit and 4WAS main control unit transmit/receive information to/from each other for opti-

mum control of the 4WAS system with the specified 4WAS system line (4WAS communication line) between
4WAS front control unit and 4WAS main control unit.

• Be careful to repair wirings because 4WAS system specified line adopt a twisted wire. Refer to 

STC-176,

"Precautions for Harness Repair"

.

DTC Logic

INFOID:0000000000958823

DTC DETECTION LOGIC

*: Communication line between 4WAS front control unit and 4WAS main control unit

DTC CONFIRMATION PROCEDURE

1.

RECHECK DTC

 With CONSULT-III

1.

Turn the ignition switch OFF to ON.

2.

Perform 4WAS front control unit self-diagnosis.

Is DTC “U1010” detected?

YES

>> Proceed to diagnosis procedure. Refer to 

STC-86, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000000958824

1.

4WAS FRONT CONTROL UNIT

Check that there is no malfunction in 4WAS front control unit harness connector or disconnection.

Is the inspection result normal? 

YES

>> Replace 4WAS front control unit. Refer to 

STC-177, "Exploded View"

.

NO

>> Repair or replace the harnesses and connectors. Refer to 

STC-176, "Precautions for Harness

Repair"

.

Special Repair Requirement

INFOID:0000000000958825

BEFORE REPLACING 4WAS FRONT CONTROL UNIT

• Record the self-diagnosis results (history).

CAUTION:

• Replace it without erasing the memory (history) of self-diagnosis results when replacing 4WAS

front control unit after diagnosis.

• Erase the memory of the self-diagnosis results (record) after printing out or recording all the val-

ues of “DATA MONITOR” when erasing the memory of the self-diagnosis results (record).

AFTER REPLACING 4WAS FRONT CONTROL UNIT

• Perform 4WAS front actuator adjustment after replacing 4WAS front control unit. Refer to 

STC-28, "4WAS

FRONT ACTUATOR NEUTRAL POSITION ADJUSTMENT : Special Repair Requirement (Pattern 3)"

.

DTC

Items

(CONSULT-III screen terms)

Diagnostic item is detected when...

Possible cause

U1010

CONTROL UNIT(CAN)

Detecting error during the initial diagnosis of 4WAS 
controller of 4WAS front control unit

4WAS communication 
line*/4WAS main control 
unit/4WAS front control 
unit error

C1900, C1901, C1906, C1907, C1927, C1933 4WAS MAIN CONTROL UNIT

STC-87

< COMPONENT DIAGNOSIS >

[WITH 4WAS]

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C1900, C1901, C1906, C1907, C1927, C1933 4WAS MAIN CONTROL UNIT

Description

INFOID:0000000000958826

• 4WAS rear actuator and the power steering solenoid valve is controlled by each sensor signal.
• The fail-safe functions stops the rear wheel angle (the front wheel is the steering wheel cutting angle) when

the electric components and the mechanical components are malfunctioning.

• The protection function mode stops 4WAS system intermittently when the input signal does not input to

4WAS main control unit.

• 4WAS front control unit and 4WAS main control unit control the best control of 4WAS system by 4WAS com-

munication line.

DTC Logic

INFOID:0000000000958827

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

RECHECK DTC

 With CONSULT-III

1.

Turn the ignition switch OFF to ON.

2.

Perform 4WAS main control unit self-diagnosis.

Is DTC “C1900”, “C1901”, “C1906”, “C1907”, “C1927” or “C1933” detected?

YES

>> Proceed to diagnosis procedure. Refer to 

STC-87, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000000958828

1.

PERFORM SELF-DIAGNOSIS (4WAS MAIN CONTROL UNIT)

 With CONSULT-III

Perform 4WAS main control unit self-diagnosis.
Is any DTC “C1900”, “C1901”, “C1906”, “C1907”, “C1927” or “C1933” detected?

YES

>> Replace 4WAS main control unit. Refer to 

STC-178, "Exploded View"

.

NO

>> GO TO 2.

2.

CHECK INFORMATION

 With CONSULT-III

Check the “DATA MONITOR” value of each DTC detected with the self-diagnosis function. Refer to 

STC-155,

"Reference Value"

.

Is each data the standard value?

YES

>> Check each harness connector pin terminal for disconnection.

DTC

Items

(CONSULT-III screen terms)

Diagnostic item is detected when...

Possible cause

C1900

CONTROL UNIT
[ABNORMAL1]

An error is detected inside 4WAS main control unit.

4WAS main control unit 
error

C1901

CONTROL UNIT
[ABNORMAL2]

An error is detected inside 4WAS main control unit.

4WAS main control unit 
error

C1906

CONTROL UNIT
[ABNORMAL5]

An error is detected inside 4WAS main control unit.

4WAS main control unit 
error

C1907

CONTROL UNIT
[ABNORMAL4]

An error is detected inside 4WAS main control unit.

4WAS main control unit 
error

C1927

CONTROL UNIT
[ABNORMAL5]

An error is detected inside 4WAS main control unit.

4WAS main control unit 
error

C1933

CONTROL UNIT

An error is detected inside 4WAS main control unit.

4WAS main control unit 
error

STC-88

< COMPONENT DIAGNOSIS >

[WITH 4WAS]

C1900, C1901, C1906, C1907, C1927, C1933 4WAS MAIN CONTROL UNIT

NO

>> Replace 4WAS main control unit. Refer to 

STC-178, "Exploded View"

.

Special Repair Requirement

INFOID:0000000000958829

BEFORE REPLACING 4WAS MAIN CONTROL UNIT

• Record the self-diagnosis results (history).

CAUTION:

• Replace it without erasing the memory (history) of self-diagnosis results when replacing 4WAS

main control unit after diagnosis.

• Erase the memory of the self-diagnosis results (record) after printing out or recording all the val-

ues of “DATA MONITOR” when erasing the memory of the self-diagnosis results (record).

C1902, C1903, C1904, C1910, C1913 4WAS REAR MOTOR OUTPUT

STC-89

< COMPONENT DIAGNOSIS >

[WITH 4WAS]

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C1902, C1903, C1904, C1910, C1913 4WAS REAR MOTOR OUTPUT

Description

INFOID:0000000000958830

• 4WAS rear motor activates 4WAS rear actuator.
• Maintain the toe-stiffness of rear wheels against the road external force because the irreversible sufficiency

performance hypoid gear is used.

DTC Logic

INFOID:0000000000958831

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

RECHECK DTC

 With CONSULT-III

1.

Perform “SELF DIAGNOSTIC MODE” item on “ACTIVE TEST” of 4WAS main control unit.

CAUTION:

Perform the active test while stopping the vehicle.

2.

Perform 4WAS main control unit self-diagnosis.

Is DTC “C1902”, “C1903”, “C1904”, “C1910” or “C1913” detected?

YES

>> Proceed to diagnosis procedure. Refer to 

STC-89, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000000958832

1.

CHECK 4WAS REAR MOTOR CIRCUIT

1.

Turn the ignition switch OFF.

2.

Disconnect 4WAS main control unit harness connector.

3.

Disconnect 4WAS rear motor harness connector.

4.

Check the continuity between 4WAS main control unit harness connector and 4WAS rear motor harness
connector.

DTC

Items

(CONSULT-III screen terms)

Diagnostic item is detected when...

Possible cause

C1902

MOTOR OUTPUT
[REV CURRENT]

4WAS rear motor current error is detected.
(4WAS rear motor current output direction differs.)

4WAS rear motor error

C1903

MOTOR OUTPUT
[NO CURRENT]

4WAS rear motor current error is detected.
(Current is input to 4WAS main control unit if 4WAS 
main control unit output is “OFF”.)

4WAS rear motor error

C1904

MOTOR OUTPUT
[OVERCURRENT]

4WAS rear motor current error is detected.
(4WAS rear motor output is overcurrent.)

4WAS rear motor error

C1910

MOTOR OUTPUT
[MOTOR LOCK]

4WAS rear motor inside error is detected.
(4WAS main motor does not move or the rear wheel an-
gle sensor does not change if 4WAS main control unit 
output is 14A or more.)

4WAS rear motor error

C1913

MOTOR OUTPUT
[ABNORML SIG]

4WAS rear motor current error is detected.
(4WAS main motor does not move or the rear wheel an-
gle sensor output does not change when 4WAS main 
control unit output is 18A or more, and 4WAS main mo-
tor output is low.)

4WAS rear motor error

4WAS main control unit

4WAS rear motor

Continuity

Connector

Terminal

Connector

Terminal

B54

38

B36

1

Existed

39

2