Infiniti QX56 (Z62). Manual - part 154

C1145, C1146 YAW RATE/SIDE/DECEL G SENSOR

BRC-101

< DTC/CIRCUIT DIAGNOSIS >

[WITH VDC]

C

D

E

G

H

I

J

K

L

M

A

B

BRC

N

O

P

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> GO TO 3.

3.

CHECK YAW RATE/SIDE/DECEL G SENSOR POWER SUPPLY CIRCUIT

1.

Turn the ignition switch OFF.

2.

Check 10A fuse (#57).

3.

Disconnect IPDM E/R harness connector.

4.

Check continuity between yaw rate/side/decel G sensor harness connector and IPDM E/R harness con-
nector.

5.

Check continuity between yaw rate/side/decel G sensor harness connector and ground.

Is the inspection result normal?

YES

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

PG-89, "Wiring Diagram - IGNITION

POWER SUPPLY -"

.

NO

>> Repair or replace error-detected parts.

4.

CHECK YAW RATE/SIDE/DECEL G SENSOR GROUND CIRCUIT

1.

Turn the ignition switch OFF.

2.

Check continuity between yaw rate/side/decel G sensor harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair or replace error-detected parts.

5.

CHECK COMMUNICATION LINE (1)

1.

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

2.

Check continuity between yaw rate/side/decel G sensor harness connector and ABS actuator and electric
unit (control unit) harness connector.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair or replace error-detected parts.

Yaw rate/side/decel G sensor

—

Voltage

Connector

Terminal

M55

3

Ground

Battery voltage

Yaw rate/side/decel G sensor

IPDM E/R

Continuity

Connector

Terminal

Connector

Terminal

M55

3

E15

59

Existed

Yaw rate/side/decel G sensor

—

Continuity

Connector

Terminal

M55

3

Ground

Not existed

Yaw rate/side/decel G sensor

—

Continuity

Connector

Terminal

M55

6

Ground

Existed

Yaw rate/side/decel G sensor

ABS actuator and electric unit (control unit)

Continuity

Connector

Terminal

Connector

Terminal

M55

4

E36

9

Existed

5

10

BRC-102

< DTC/CIRCUIT DIAGNOSIS >

[WITH VDC]

C1145, C1146 YAW RATE/SIDE/DECEL G SENSOR

6.

CHECK COMMUNICATION LINE (2)

1.

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

2.

Check resistance between yaw rate/side/decel G sensor harness connector terminals.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace ABS actuator and electric unit (control unit). Refer to 

BRC-137, "Removal and Installa-

tion"

.

7.

CHECK COMMUNICATION LINE (3)

1.

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

2.

Check continuity between yaw rate/side/decel G sensor harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Repair or replace error-detected parts.

8.

CHECK TERMINAL

• Check ABS actuator and electric unit (control unit) pin terminals for damage or loose connection with har-

ness connector.

• Check yaw rate/side/decel G sensor pin terminals for damage or loose connection with harness connector.
• Check IPDM E/R pin terminals for damage or loose connection with harness connector.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Repair or replace error-detected parts.

9.

REPLACE YAW RATE/SIDE/DECEL G SENSOR

With CONSULT-III.

1.

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

2.

Connect IPDM E/R harness connector.

3.

Replace yaw rate/side/decel G sensor. Refer to 

BRC-138, "Removal and Installation"

.

4.

Erase Self-diagnosis result for “ABS”.

5.

Turn the ignition switch OFF.

6.

Turn the ignition switch ON.

CAUTION:

Never start engine.

7.

Perform self-diagnosis for “ABS”.

Is DTC “C1145” or “C1146” detected?

YES

>> Replace ABS actuator and electric unit (control unit). Refer to 

BRC-137, "Removal and Installa-

tion"

.

NO

>> INSPECTION END

Yaw rate/side/decel G sensor

Resistance

Connector

Terminal

M55

4 

100 – 140 

Ω

5

Yaw rate/side/decel G sensor

Ground

Continuity

Connector

Terminal

M55

4

—

Not existed

5

C1155 BRAKE FLUID LEVEL SWITCH

BRC-103

< DTC/CIRCUIT DIAGNOSIS >

[WITH VDC]

C

D

E

G

H

I

J

K

L

M

A

B

BRC

N

O

P

C1155 BRAKE FLUID LEVEL SWITCH

DTC Logic

INFOID:0000000006222625

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

CHECK DTC DETECTION

With CONSULT-III.

1.

Turn the ignition switch OFF to ON, and then wait 1 minute or more.

2.

Perform self-diagnosis for “ABS”.

Is DTC “C1155” detected?

YES

>> Proceed to diagnosis procedure. Refer to 

BRC-103, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000006222626

1.

CHECK BRAKE FLUID LEVEL

1.

Turn the ignition switch OFF.

2.

Check brake fluid level. Refer to 

BR-10, "Inspection"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Refill brake fluid. Refer to 

BR-11, "Refilling"

.

2.

CHECK BRAKE FLUID LEVEL SWITCH HARNESS

1.

Disconnect brake fluid level switch harness connector.

2.

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

3.

Check continuity between brake fluid level switch harness connector and ABS actuator and electric unit
(control unit) harness connector.

4.

Check continuity between brake fluid level switch harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair or replace error-detected parts.

3.

CHECK BRAKE FLUID LEVEL SWITCH GROUND

Check continuity between brake fluid level switch harness connector and ground.

DTC

Display Item

Malfunction detected condition

Possible causes

C1155

BR FLUID LEVEL LOW

• When brake fluid level low signal is detected.
• When an open circuit is detected in brake fluid level 

switch circuit.

• Harness or connector
• ABS actuator and electric unit 

(control unit)

• Brake fluid level switch

Brake fluid level switch

ABS actuator and electric unit (control unit)

Continuity

Connector

Terminal

Connector

Terminal

E47

1

E36

13

Existed

Brake fluid level switch

—

Continuity

Connector

Terminal

E47

1

Ground

Not existed

BRC-104

< DTC/CIRCUIT DIAGNOSIS >

[WITH VDC]

C1155 BRAKE FLUID LEVEL SWITCH

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace error-detected parts.

4.

CHECK BRAKE FLUID LEVEL SWITCH

Check brake fluids level witch. Refer to 

BRC-104, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace reservoir tank. Refer to 

BR-30, "Disassembly and Assembly"

.

5.

CHECK TERMINAL

• Check brake fluid level switch pin terminals for damage or loose connection with harness connector.
• Check ABS actuator and electric unit (control unit) pin terminals for damage or loose connection with har-

ness connector.

Is the inspection result normal?

YES

>> Replace ABS actuator and electric unit (control unit). Refer to 

BRC-137, "Removal and Installa-

tion"

.

NO

>> Repair or replace error-detected parts.

Component Inspection

INFOID:0000000006222627

1.

CHECK BRAKE FLUID LEVEL SWITCH

1.

Turn the ignition switch OFF.

2.

Disconnect brake fluid level switch harness connector.

3.

Check resistance between terminals of brake fluid level switch.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace reservoir tank. Refer to 

BR-30, "Disassembly and Assembly"

.

Brake fluid level switch

—

Continuity

Connector

Terminal

E47

2

Ground

Existed

Brake fluid level switch

Condition

Resistance

Terminal

1 – 2

When brake fluid level in reservoir tank is within the specified level.

1.9 – 2.1 k

Ω

When brake fluid level in reservoir tank is less than the specified 
level.

1.0 

Ω

 or less