2011 INFINITI QX56 brake fluid

BRC-42
< SYSTEM DESCRIPTION >[WITH VDC]
DIAGNOSIS SYSTEM [
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL
UNIT)]
Note 1: Refer to BRC-16, "System Description" for ON/OFF conditions of each warning lamp and indicator
lamp.
Note 2: Models with 4WD System
Note 3: Models with Advanced Driver Assistance System
Note 4: USS means “hill start assist”
ACTIVE TEST
The active test is used to determine and identify details of a malfunction, based on self-diagnosis test result
sand data obtained in the DATA MONITOR. In response to instructions from CONSULT-III, instead of those
SV2
(On/Off) Suction valve 2 operation status is displayed.
STOP LAMP SW2
(On/Off) Stop lamp switch signal input status is displayed.
ACCEL POS SIG
(%) ×
Displays the Accelerator pedal position
SIDE G-SENSOR
(m/s
2) ×
Side G detected by side G sensor is displayed.
STR ANGLE SIG
( ° ) ×
Steering angle detected by steering angle sensor is dis-
played.
PRESS SENSOR
(bar) ×Detects the brake fluid pressure of master cylinder part is
displayed.
ACCUM PRESS SEN
(bar) Detects the brake fluid pressure of accumulator is dis-
played.
CONT PRESS SEN
(Note 3)
(bar) Detects the brake fluid pressure of control pressure sensor
is displayed
EBD SIGNAL
(On/Off) EBD operation status is displayed.
ABS SIGNAL
(On/Off) ABS operation status is displayed.
TCS SIGNAL
(On/Off) TCS operation status is displayed.
VDC SIGNAL
(On/Off) VDC operation status is displayed.
EBD FAIL SIG
(On/Off) EBD fail-safe signal status is displayed.
ABS FAIL SIG
(On/Off) ABS fail-safe signal st
atus is displayed.
TCS FAIL SIG
(On/Off) TCS fail-safe signal status is displayed.
VDC FAIL SIG
(On/Off) VDC fail-safe signal status is displayed.
CRANKING SIG
(On/Off) Cranking status is displayed.
FLUID LEV SW
(On/Off) ×Brake fluid level signal input status via CAN communication
is displayed.
PARK BRAKE SW
(On/Off) ×Parking brake switch signal input status via CAN communi-
cation is displayed.
STP ON RLY
(On/Off) Stop lamp switch relay status is displayed.
USS SIG
(Note 4)
(On/Off) hill start assist operation status is displayed.
Item (Unit)
Monitor item selection
Note
INPUT SIGNALS MAIN ITEMS
Revision: 2010 May2011 QX56

ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)BRC-47
< ECU DIAGNOSIS INFORMATION > [WITH VDC]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
Note 1: Confirm tire pressure is standard value.
Note 2: Refer to BRC-16, "
System Description" for ON/Blinking/OFF conditions of each warning lamp and indi-
cator lamp.
Note 3: Models with 4WD System
Note 4: Models with Advanced Driver Assistance System
Note 5: USS means “hill start assist”.
Fail-safeINFOID:0000000006222580
VDC FUNCTION, TCS FUNCTION, hill start assi st FUNCTION AND BRAKE LIMITED SLIP DIFFER-
ENTIAL (BLSD) FUNCTION
VDC warning lamp in combination meter turn ON w hen a malfunction occurs in system [ABS actuator and
electric unit (control unit)]. The control is suspended for VDC function, TCS function, hill start assist function
and brake limited slip differential (BLSD) function. T he Vehicle status becomes the same as models without
PRESS SENSORBrake pedal not depressed Approx. 0 bar
Brake pedal depressed (
−40) – (+300) bar
ACCUM PRESS SEN With ig nition switch ON Approx. 0 – 210 bar (Proportional to the
amount of accumulated pressure in the
accumulator)
CONT PRESS SEN
(Note 4)Brake pedal not depressed Approx. 0 bar
Brake pedal depressed ( −40) – (+300) bar
EBD SIGNAL EBD is active On
EBD is inactive Off
ABS SIGNAL ABS is active On
ABS is inactive Off
TCS SIGNAL TCS is active On
TCS is inactive Off
VDC SIGNAL VDC is active On
VDC is inactive Off
EBD FAIL SIG In EBD fail-safe On
EBD is normal Off
ABS FAIL SIG In ABS fail-safe On
ABS is normal Off
TCS FAIL SIG In TCS fail-safe On
TCS is normal Off
VDC FAIL SIG In VDC fail-safe On
VDC is normal Off
CRANKING SIG At cranking On
Other than at cranking Off
FLUID LEV SW When brake fluid level switch is ON (brake fluid level
is less than the specified level)
On
When brake fluid level switch is OFF Off
PARK BRAKE SW When parking brake is active On
Parking brake is released Off
STP ON RLY Stop lamp relay is active On
Stop lamp relay is inactive Off
USS SIG
(Note 5)hill start assist is active On
hill start assist is inactive Off
Monitor item Condition Reference values in normal operation
Revision: 2010 May2011 QX56

ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)BRC-49
< ECU DIAGNOSIS INFORMATION > [WITH VDC]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
C 111 5 When difference in wheel speed between any wheel and others is detected during
the vehicle is driven, because of installation of other tires than specified. The following functions are sus-
pended.
 VDC function
 TCS function
 ABS function
 hill start assist function
 Brake limited slip differential
(BLSD) function
C 111 6
 When stop lamp switch signal is not input when brake pedal depress.
 When stop lamp switch signal is not input when stop lamp relay operates.
C 111 8
*1When a malfunction is detected in transfer control unit system.
C1120 When a malfunction is detec ted in front LH ABS IN valve.
The following functions are sus-
pended.
 VDC function
 TCS function
 ABS function
 EBD function
 hill start assist function
 Brake limited slip differential (BLSD) function
C1121 When a malfunction is detec
ted in front LH ABS OUT valve.
C1122 When a malfunction is detected in front RH ABS IN valve.
C1123 When a malfunction is det ected in front RH ABS OUT valve.
C1124 When a malfunction is detected in rear LH ABS IN valve.
C1125 When a malfunction is detected in rear LH ABS OUT valve.
C1126 When a malfunction is det ected in rear RH ABS IN valve.
C1127 When a malfunction is detected in rear RH ABS OUT valve.
C1130 When a malfunction is detected in ECM system. The following functions are sus-
pended.
 VDC function
 TCS function
 hill start assist function
 Brake limited slip differential
(BLSD) function
C1140 When a malfunction is detected in actuator relay. The following functions are sus-
pended.
 VDC function
 TCS function
 ABS function
 EBD function
 hill start assist function
 Brake limited slip differential
(BLSD) function
C1142
*2When a malfunction is detected in master cylinder pressure sensor or control pres-
sure sensor. The following functions are sus-
pended.
 VDC function
 TCS function
 hill start assist function
 Brake limited slip differential
(BLSD) function
C1143 When a malfunction is detected in steering angle sensor.
C1144 When neutral position adjustment of steering angle sensor is not complete.
C1145
 When a malfunction is detected in yaw rate signal.
 When yaw rate signal is not continuously received for 2 seconds or more.
 When side G signal is not continuously received for 2 seconds or more.
 When decel G signal is not continuously received for 2 seconds or more.
The following functions are sus-
pended.
 VDC function
 TCS function
 ABS function
 hill start assist function
 Brake limited slip differential
(BLSD) function
C1146 When a malfunction is detected in side/decel G signal.
C1155
 When brake fluid level low signal is detected.
 When an open circuit is detected in brake fluid level switch circuit.
C1160 When calibration of yaw rate/side/decal G sensor is not complete.
C1164 When a malfunction is detected in cut valve 1. The following functions are sus- pended.
 VDC function
 TCS function
 ABS function
 EBD function
 hill start assist function
 Brake limited slip differential (BLSD) function
C1165 When a malfunction is detected in cut valve 2.
C1166 When a malfunction is detected in suction valve 1.
C1167 When a malfunction is detected in suction valve 2. DTC Malfunction detected condition Fail-safe condition
Revision: 2010 May2011 QX56

BRC-50
< ECU DIAGNOSIS INFORMATION >[WITH VDC]
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
*1: Models with 4WD System
*2: Models with Advanced Driver Assistance System
Protection FunctionINFOID:0000000006222581
The VDC warning lamp, ABS warning lamp and brake warning lamp turns ON and DTC “C118E” may be
detected in self-diagnosis result of “ABS” when the br
ake pedal is excessively operated, such as air bleeding.
This is not a system malfunction because this occurs due to the temporary decrease in accumulator fluid pres-
sure. The system returns to normal condition when the accu mulator fluid pressure reaches the specified pres-
sure with the ignition switch ON and the VDC warning lamp, ABS warning lamp, and brake warning lamp turn
OFF. After these steps, erase self-diagnos is results for “ABS” with CONSULT-III.
NOTE:
D T C “ C 1111 ” i s d e t e c t e d i n s e l f - d i agnosis results of “ABS” when the a ccumulator system has a malfunction.
DTC Inspection Priority ChartINFOID:0000000006222582
When multiple DTCs are displayed simultaneously, check one by one depending on the following priority list.
C1170 When the information in ABS actuator and electric unit (control unit) is not the same. The following functions are sus-
pended.
 VDC function
 TCS function
 ABS function
 hill start assist function
 Brake limited slip differential
(BLSD) function
C118E When performing excessive brake pedal operation with the vehicle stopped. [When
accumulator fluid pressure reaches 11.43 MPa (114 bar, 116.6 kg/cm
2, 1657 psi) af-
ter reaching 17.3 MPa (173 bar, 176.5 kg/cm2, 2509 psi.] The following functions are sus-
pended.
 VDC function
 TCS function
 ABS function
 EBD function
 hill start assist function
 Brake limited slip differential
(BLSD) function
U1000 When CAN communication signal is not continuously received for 2 seconds or
more. The following functions are sus-
pended.
 VDC function
 TCS function
 ABS function
 hill start assist function
 Brake limited slip differential
(BLSD) function
DTC Malfunction detected condition Fail-safe condition
DTC
 VDC warning lamp
 ABS warning lamp
 Brake warning lamp Condition Description protection function
C118E ON When temporary decrease in accumulator fluid pres-
sure.
NOTE:
System is not malfunction. The following functions are suspended
temporarily
 VDC function
 TCS function
 ABS function
 EBD function
 hill start assist function
 Brake limited slip differential (BLSD)
function
Priority Detected item (DTC)
1  U1000 CAN COMM CIRCUIT
2  C1170 VARIANT CODING
Revision: 2010 May2011 QX56

C1142 PRESS SENSORBRC-95
< DTC/CIRCUIT DIAGNOSIS > [WITH VDC]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
C1142 PRESS SENSOR
DTC LogicINFOID:0000000006222617
DTC DETECTION LOGIC
*: Models with Advanced Driver Assistance System
DTC CONFIRMATION PROCEDURE
1.CHECK DTC DETECTION
With CONSULT-III.
1. Turn the ignition switch OFF to ON.
2. Perform self-diagnosis for “ABS”.
Is DTC
“C1142” detected?
YES >> Proceed to diagnosis procedure. Refer to BRC-95, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222618
1.CHECK STOP LAMP SWITCH SUSTEM
Check stop lamp switch system. Refer to BRC-79, "
Diagnosis Procedure".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace error-detected parts.
2.CHECK BRAKE FLUID LEACKAGE
Check brake fluid leakage. Refer to BR-10, "
Inspection".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace error-detected parts.
3.CHECK BRAKE PIPING
Check brake piping. Refer to BR-24, "
FRONT : Inspection" (front), BR-26, "REAR : Inspection" (rear).
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
4.CHECK BRAKE PEDAL
Check brake pedal. Refer to BR-21, "
Inspection and Adjustment".
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace error-detected parts.
5.CHECK HYDRAULIC BOOSTER ASSEMBLY
Check hydraulic booster assembly. Refer to BR-32, "
Inspection and Adjustment".
Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair or replace error-detected parts.
6.CHECK FRONT DISC BRAKE
Check front disc brake. Refer to BR-39, "
BRAKE CALIPER ASSEMBLY : Inspection".
DTC Display Item Malfunction detected condition Possible causes
C1142 PRESS SEN CIRCUIT When a malfunction is detected in master cylinder
pressure sensor or control pressure sensor
*. Stop lamp switch system
 ABS actuator and electric unit
(control unit)
 Brake system
Revision: 2010 May2011 QX56

C1155 BRAKE FLUID LEVEL SWITCHBRC-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 LogicINFOID: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 ProcedureINFOID: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
Revision: 2010 May2011 QX56

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 electr ic unit (control unit). Refer to BRC-137, "Removal and Installa-
tion".
NO >> Repair or replace error-detected parts.
Component InspectionINFOID: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
Te r m i n a l
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
Revision: 2010 May2011 QX56

C118E ACCUMULATORBRC-111
< DTC/CIRCUIT DIAGNOSIS > [WITH VDC]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
C118E ACCUMULATOR
DTC LogicINFOID:0000000006222636
DTC DETECTION LOGIC
CAUTION:
The VDC warning lamp, ABS warning lamp and br ake warning lamp turns ON and DTC “C118E” may
be detected in self-diagnosis result of “ABS” when the brake pedal is excessively operated, such as
air bleeding. This is not a system malfunction because this occurs due to the temporary decrease in
accumulator fluid pressure. The system returns to normal condition when the accumulator fluid pres-
sure reaches the specified pressure with the ignition switch ON and the VDC warning lamp, ABS warn-
ing lamp, and brake warning lamp turn OFF. After these steps, ABS self-diagnosis results are erased.
Diagnosis ProcedureINFOID:0000000006222637
1.ERASE SELF-DIAGNOSIS RESULT
CAUTION:
The VDC warning lamp, ABS warning lamp and br ake warning lamp turns ON and DTC “C118E” may
be detected in self-diagnosis result of “ABS” when the brake pedal is excessively operated, such as
air bleeding. This is not a system malfunction because this occurs due to the temporary decrease in
accumulator fluid pressure. The system returns to normal condition when the accumulator fluid pres-
sure reaches the specified pressure with the ignition switch ON and the VDC warning lamp, ABS warn-
ing lamp, and brake warning lamp turn OFF. After these steps, ABS self-diagnosis results are erased.
With CONSULT-III.
1. Erase Self-diagnosis result for “ABS”.
2. Turn the ignition switch OFF.
3. Depress brake pedal to full stroke 20 times or more.
4. Start the engine, and then wait 2 minutes or more.
5. Check VDC warning lamp, ABS warning lamp and brake warning lamp turns OFF.
6. Perform self-diagnosis for “ABS”.
Is any DTC detected?
YES >> Check the DTC. Refer to BRC-51, "DTC Index".
NO >> INSPECTION END
DTC Display Item Malfunction detected condition Possible causes
C118E ACCUMULATOR PRESS When performing excessive brake pedal operation
with the vehicle stopped. [When accumulator fluid
pressure reaches 11.43 MPa (114 bar, 116.6 kg/cm
2,
1657 psi) after reaching 17.3 MPa (173 bar, 176.5 kg/
cm
2, 2509 psi.] —
Revision: 2010 May2011 QX56