Brake booster INFINITI QX56 2008 Factory Owner's Manual

ABS
BRC-19
< FUNCTION DIAGNOSIS > [VDC/TCS/ABS]
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Component Parts LocationINFOID:0000000001691095
1. Front wheel sensor LH E18 Front wheel sensor RH E117 2. Delta stroke sensor E114 3. Brake fluid level switch E21
4. Active booster E49 5. Front pressure sensor E31 6. Rear pressure sensor E32
7. ABS actuator and electric unit (con- trol unit) E125 8. Stop lamp switch E38
9. Combination meter M23, M24
AWFIA0713GB
Revision: March 2010 2008 QX56

BRC-22
< FUNCTION DIAGNOSIS >[VDC/TCS/ABS]
EBD
Component Parts Location
INFOID:0000000001691097
1. Front wheel sensor LH E18 Front wheel sensor RH E117 2. Delta stroke sensor E114
3. Brake fluid level switch E21
4. Active booster E49 5. Front pressure sensor E316. Rear pressure sensor E32
7. ABS actuator and el ectric unit (con-
trol unit) E125 8. Stop lamp switch E38
9. Combination meter M23, M24
AWFIA0713GB
Revision: March 2010 2008 QX56

BRC-26
< FUNCTION DIAGNOSIS >[VDC/TCS/ABS]
DIAGNOSIS SYSTEM [
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL
UNIT)]
CV1
(ON/OFF) ––× Front side switch-over solenoid
valve (cut valve) (ON/OFF) status is
displayed.
CV2
(ON/OFF) ––× Rear side switch-over solenoid
valve (cut-valve) (O
N/OFF) status is
displayed.
SV1
(ON/OFF) ––× Front side switch-over solenoid
valve (suction valve) (ON/OFF) sta-
tus is displayed.
SV2
(ON/OFF) ––× Rear side switch-over solenoid
valve (suction valve) (ON/OFF) sta-
tus is displayed.
VDC FAIL SIG
(ON/OFF) ––× VDC fail signal (ON/OFF) status is
displayed.
TCS FAIL SIG
(ON/OFF) ––× TCS fail signal (ON/OFF) status is
displayed.
ABS FAIL SIG
(ON/OFF) ––×
ABS fail signal (ON/OFF) status is
displayed.
EBD FAIL SIG
(ON/OFF) ––× EBD fail signal (ON/OFF) status is
displayed.
FLUID LEV SW
(ON/OFF) ×
– ×Brake fluid level switch (ON/OFF)
status is displayed.
EBD SIGNAL
(ON/OFF) ––×
EBD operation (ON/OFF) status is
displayed.
ABS SIGNAL
(ON/OFF) ––× ABS operation (ON/OFF) status is
displayed.
TCS SIGNAL
(ON/OFF) ––× TCS operation (ON/OFF) status is
displayed.
VDC SIGNAL
(ON/OFF) ––×
VDC operation (ON/OFF) status is
displayed.
EBD WARN LAMP –– ×Brake warning lamp (ON/OFF) sta-
tus is displayed.
SLCT LVR POSI ××× Shift position judged by transmis-
sion range switch signal.
R POSI SIG ––×Shift position judged by transmis-
sion range switch signal.
2WD/4WD ––×It recognizes on software whether it
is 2WD and whether it is in 4WD
state.
BST OPER SIG ––×Active booster operation (ON/OFF)
st
atus is
di

splayed.
PRESS SENSOR ×– ×Brake pressure detected by pres-
sure sensor is displayed.
CRANKING SIG ––×The input state of the key SW
START position signal is displayed.
PRESS SEN 2 ––×Brake pressure detected by pres-
sure sensor is displayed.
DELTA S SEN ––×The amount of stroke sensor move-
ments in the active booster detected
by DELTA S SEN is displayed.
Item
(Unit) Data monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELECTION
FROM MENU
Revision: March 2010 2008 QX56

BRC-28
< FUNCTION DIAGNOSIS >[VDC/TCS/ABS]
DIAGNOSIS SYSTEM [
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL
UNIT)]
*: ON for 1 to 2 seconds after the touch, and then OFF
ABS MOTOR• Touch “ON” and “OFF” on screen. Make sure motor relay and actuator relay operates as shown in table
below.
BOOSTER DRIVE
• Touch “UP” and “DOWN” on the screen. Check that booster drive operates as shown in table below.
CAUTION:
Perform active test subject to the conditions below.
• Do not operate brake pedal during active test.
• Make sure the engine revo lution is over 500 rpm.
• Make sure the vehicle is not moving.
RR RH SOL
RR RH ABS SOLE-
NOID (ACT) RR RH IN SOL
OFF ON ON OFF OFF OFF
RR RH OUT SOL OFF OFF ON* OFF OFF OFF
RR LH SOL
RR LH ABS SOLE-
NOID (ACT) RR LH IN SOL
OFF ON ON OFF OFF OFF
RR LH OUT SOL OFF OFF ON* OFF OFF OFF
REAR SOL RR RH IN SOL
OFF ON ON OFF OFF OFF
RR RH OUT SOL OFF OFF ON* OFF OFF OFF
RR LH IN SOL OFF ON ON OFF OFF OFF
RR LH OUT SOL OFF OFF ON* OFF OFF OFF
Operation ONOFF
MOTOR RELAY ONOFF
ACTUATOR RLY ONON
Operation UPDOWN
STOP LAMP SW ONOFF
BST OPER SIG ONOFF
PRESS SENSOR 50 ± 5 bar 0 bar
PRESS SEN 2 50 ± 5 bar 0 bar
STP OFF RLY OFFOFF
Operation
ABS solenoid valve
ABS solenoid valve (ACT)
UP KEEP DOWN UP ACTUA-
TOR UP ACTUA-
TOR KEEP
Revision: March 2010 2008 QX56

C1178, C1181, C1184, C1189 ABS ACTIVE BOOSTER
BRC-73
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
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C1178, C1181, C1184, C1189 ABS ACTIVE BOOSTER
DescriptionINFOID:0000000001686340
The active brake booster consists of a vacuum boos ter, an active booster control group and a delta stroke
sensor. If a brake booster system malfunction occurs due to loss of vacuum, the delta stroke sensor will signal
the ABS actuator and electric unit (control unit) that a booster malfunction has occurred. The active booster
then applies supplemental force to the master cylinder re lative to the amount of force exerted on the brake
pedal.
DTC LogicINFOID:0000000001686341
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to BRC-73, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000001686342
INSPECTION PROCEDURE
1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the active booster connector E49 and ABS ac tuator and electric unit (control unit) connector
E125 and inspect the terminals for deforma tion, disconnection, looseness, or damage.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair connector.
2.ACTIVE BOOSTER CIRCUIT INSPECTION
DTC Display item Malfunction detected condition Possible cause
C1178 ABS ACTIVE BOOSTER SV
NG Active booster solenoid is malfunctioning, or signal line of
active booster servo is open or shorted.
• Harness or connector
• Active booster
• ABS actuator and electric unit (control unit)
C1181
ABS ACTIVE BOOSTER RE-
SPONSE NG Active booster response is malfunctioning, or signal line
of active booster response is open or shorted.
C1184 ABS BRAKE RELEASE SW
NG Brake release switch is malfunctioning, or signal line of
brake release switch is open or shorted.
C1189 ABS BRAKE BOOSTER DE-
FECT Brake booster is defective or malfunctioning.
Self-diagnosis results
ABS ACTIVE BOOSTER SV NG
ABS ACTIVE BOOSTER RESPONSE NG ABS BRAKE RELEASE SW NG
ABS BRAKE BOOSTER DEFECT
Revision: March 2010 2008 QX56

BRC-74
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1178, C1181, C1184, C1
189 ABS ACTIVE BOOSTER
1. Measure the continuity between ABS actuator and electric unit
(control unit) harness connector E125 (A) and active booster
harness connector E49 (B).
2. Measure the continuity between ABS actuator and el ectric unit (control unit) harness connector E125 (A)
and body ground.
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace harness or connector.
3.ACTIVE BOOSTER INSPECTION
1. Reconnect the active booster and ABS actuator and electric unit (control unit) connectors.
2. Use “DATA MONITOR” to check if the status of “RELEASE SWITCH NO” and “RELEASE SWITCH NC” is
normal.
Is the inspection result normal?
YES >> Replace the ABS actuator and electric unit (control unit). Refer to BRC-116, "Removal and Instal-
lation".
NO >> Replace the active booster. Refer to BR-26, "
Removal and Installation".
Component InspectionINFOID:0000000001686343
1.CHECK DATA MONITOR
Use “DATA MONITOR” to check if the status of “RELEASE SWITCH NO” and “RELEASE SWITCH NC” is nor-
mal.
ABS actuator and electric unit (control unit) Active booster
Continuity
Connector Terminal Connector Terminal
A: E125 17
B: E49 3
Ye s
27
1
28 5
30 2
31 4
ABS actuator and electric unit (control unit) —Contin u it y
Connector Terminal
A: E125 17
Ground No
27
28
30
31
AWFIA0028ZZ
Condition
RELEASE SWITCH NO
(DATA MONITOR) RELEASE SWITCH NC
(DATA MONITOR)
When brake pedal is depressed. ONOFF
When brake pedal is released. OFFON
ConditionRELEASE SWITCH NO
(DATA MONITOR) RELEASE SWITCH NC
(DATA MONITOR)
When brake pedal is depressed. ONOFF
When brake pedal is released. OFFON
Revision: March 2010 2008 QX56

BRC-76
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1179 ABS DELTA S SEN NG
C1179 ABS DELTA S SEN NG
DescriptionINFOID:0000000001686345
The active brake booster consists of a vacuum booster, an active booster control group and a delta stroke
sensor. If a brake booster system malfunction occurs due
to loss of vacuum, the delta stroke sensor will signal
the ABS actuator and electric unit (c ontrol unit) that a booster malfunction has occurred. The active booster
then applies supplemental force to the master cylinder re lative to the amount of force exerted on the brake
pedal.
DTC LogicINFOID:0000000001686346
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to BRC-76, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000001686347
INSPECTION PROCEDURE
1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the delta stroke sensor connector E114 and ABS actuator and electric unit (control unit) con- nector E125 and inspect the terminals for def ormation, disconnection, looseness, or damage.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair connector.
2.DELTA STROKE SENSOR CIRCUIT INSPECTION
1. Measure the continuity between ABS actuator and electric unit (control unit) harness connector E125 (A) and delta stroke sen-
sor harness connector E114 (B).
2. Measure the continuity between ABS actuator and el ectric unit (control unit) harness connector E125 (A)
and body ground.
DTC Display item Malfunction detected condition Possible cause
C1179 ABS DELTA S SEN NG Delta stroke sensor is malfunctioning, or signal line of
delta stroke sensor is open or shorted. • Harness or connector
• Delta stroke sensor
• ABS actuator and electric unit
(control unit)
Self-diagnosis results
ABS DELTA S SEN NG
ABS actuator and electric unit (control unit) Delta stroke sensor
Continuity
Connector Terminal Connector Terminal
A: E125 26
B: E114 1
Ye s
39 3
40 5
AWFIA0029ZZ
Revision: March 2010 2008 QX56

BRC-78
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1185 ICC UNIT
C1185 ICC UNIT
DescriptionINFOID:0000000001691164
When the force applied to brake pedal exceeds a certain level, the brake assist is activated and generates a
greater braking force than that of a convent
ional brake booster, even with light pedal force.
When the ICC preview function identifies the need to apply the sudden brake by sensing the vehicle ahead in
the same lane and the distance and relative speed from it, it applies the brake pre-pressure before driver
depresses the brake pedal and improves brake response by reducing its free play.
DTC LogicINFOID:0000000001691165
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to BRC-78, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000001691166
INSPECTION PROCEDURE
1.SELF-DIAGNOSIS RESULT CHECK
Perform self-diagnosis of ICC unit.
Are self-diagnosis result items displayed?
YES >> After checking and repairing the applicable item, perform ICC unit self-diagnosis again.
NO >> GO TO 2
2.CONNECTOR INSPECTION
Disconnect the ABS actuator and electric unit (contro l unit) connector and the ICC unit connector and check
the terminals for deformation, disconnection, looseness or damage.
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace as necessary.
3.ICC UNIT CIRCUIT INSPECTION
DTC Display item Malfunction detected condition Possible cause
C1185 ABS ACC CU INTERNAL NG ICC cont rol unit internal malfunction.• Harness or connector
• ICC unit
• ABS actuator and electric unit
(control unit)
Self-diagnosis results
ABS ACC CU INTERNAL NG
Revision: March 2010 2008 QX56

ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)BRC-91
< ECU DIAGNOSIS > [VDC/TCS/ABS]
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NOTE:
• 1: Confirm tire pr essure is normal.
• 2: Only 4WD models.
• 3: On and off timing for warning lamp and indicator lamp.
- ABS warning lamp: Refer to BRC-83, "
Description".
- Brake warning lamp: Refer to BRC-84, "
Description".
- VDC OFF indicator lamp: Refer to BRC-85, "
Description".
- SLIP indicator lamp: Refer to BRC-86, "
Description".
TERMINAL LAYOUT
DELTA S SEN Value detected by delta stroke sensor When brake pedal is depressed 1.05 - 1.80 mm
When brake pedal is released
0.00 mm (+0.6/-0.4)
RELEASE SWITCH
NO Active booster signal status When brake pedal is depressed
ON
When brake pedal is released OFF
RELEASE SWITCH
NC Active booster signal status When brake pedal is depressed
OFF
When brake pedal is released ON
STP OFF RLY Stop lamp relay signal When stop lamp relay is ON
ON
When stop lamp relay is OFF OFF
PRES CTRL ACC This item is not used for this model. ——
PRES FAIL ACC This item is not used for this model. ——
Monitor item
Display content Data monitor
Condition Reference value in
normal operation
AWFIA0032ZZ
Revision: March 2010 2008 QX56

ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)BRC-101
< ECU DIAGNOSIS > [VDC/TCS/ABS]
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C1145 YAW RATE SENSOR
BRC-40, "Description"C1146SIDE G-SEN CIRCUIT
C1155 BR FLUID LEVEL LOW BRC-64, "
Description"
C1156ST ANG SEN COM CIR BRC-67, "Description"
C1160DECEL G SEN SET BRC-68, "Description"
C1163ST ANGL SEN SAFE BRC-69, "Description"
C1164CV1
BRC-70, "
Description"C1165CV2
C1166 SV1
C1167 SV2
C1170 VARIANT CORDING BRC-37, "
DTC Logic"
C1178ABS ACTIVE BOOSTER SV NG BRC-73, "Description"
C1179ABS DELTA S SEN NG BRC-76, "Description"
C1181ABS ACTIVE BOOSTER RESPONSE NG
BRC-73, "Description"C1184ABS BRAKE RELEASE SW NG
C1185 ABS ACC CU INTERNAL NG BRC-78, "
Description"
C1189ABS BRAKE BOOSTER DEFECT BRC-73, "Description"
U1000CAN COMM CIRCUIT BRC-80, "Description"
DTCItems (CONSULT screen terms) Reference
Revision: March 2010 2008 QX56