2011 INFINITI QX56 ABS

BCS-54
< ECU DIAGNOSIS INFORMATION >
BCM
*: For Canada
Fail-safeINFOID:0000000006274820
FAIL-SAFE CONTROL BY DTC
BCM performs fail-safe control when any DTC are detected.
102
(BR) Ground P/N position Input Selector lever P or N position 12 V
Except P and N positions 0 V
104
(R/B) Ground A/T shift selector
(detention switch)
power supply Output Ignition switch ON 12 V
105
(O/L) Ground Stop lamp switch 2 Input Ignition switch OFF Battery voltage
106
(Y/G) Ground
Blower fan motor re-
lay control Output Ignition switch OFF or ACC 0 V
ON 12 V
107 (L) Ground
Steering lock condi-
tion No. 1 Input Steering lock LOCK status 0 V
UNLOCK status 12 V
108 (P) Ground
Steering lock condi-
tion No. 2 Input Steering lock LOCK status 12 V
UNLOCK status 0 V
109
(L/W) Ground ACC indicator lamp Output Ignition switch OFF (LOCK indicator is
not illuminated)
Battery voltage
ACC 0 V
Te r m i n a l N o .
(Wire color) Description
Condition Va l u e
(Approx.)
Signal name Input/
Output
+ −
Display contents of CONSULT Fail-safe Cancellation
B2013: ID DISCORD BCM-S/ L Inhibit engine cranking When communication between BCM and steering lock unit are commu-
nicated normally.
B2014: CHAIN OF S/L-BCM Inhibit engine cranking When communication between BCM and steering lock unit are commu-
nicated normally.
B2192: ID DISCORD BCM-ECM Inhibit engine cranking Erase DTC
B2193: CHAIN OF BCM-ECM Inhibit engine cranking Erase DTC
B2195: ANTI-SCANNING Inhibit engine cranking Ignition switch ON → OFF
B2198: NATS ANTENNA AMP Inhibit engine cranking Erase DTC
B2557: VEHICLE SPEED In hibit steering lockWhen the following CAN signal status (vehicle speed signal) becomes
consistent
 Vehicle speed signal (ABS)
 Vehicle speed signal (Meter)
B2601: SHIFT POSITION Inhibit steering lock 500 ms after the following signal reception status becomes consistent
 Selector lever P position switch signal
 P range signal (CAN)
B2602: SHIFT POSITION Inhibit steering lock 5 seconds after the following BCM recognition conditions are fulfilled
 Ignition switch is in the ON position
 Selector lever P position switch signal: Except P position (battery volt-
age)
 Vehicle speed: 4 km/h (2.5 MPH) or more
Revision: 2010 May2011 QX56

BCS-72
< DTC/CIRCUIT DIAGNOSIS >
U0415 VEHICLE SPEED
U0415 VEHICLE SPEED
DescriptionINFOID:0000000006274834
U0415 is displayed if any unusual condition is present in the reception status of the vehicle speed signal from
the ABS actuator and electric unit (control unit).
DTC LogicINFOID:0000000006274835
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION
1. Erase the DTC.
2. Turn ignition switch OFF.
3. Perform the “Self Diagnostic Result” of BCM with CONS ULT-III, when passed 2 seconds or more after the
ignition switch is turned ON.
Is any DTC detected?
YES >> Refer to BCS-72, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006274836
1.ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAG RESULTS
Perform “Self-Diagnostic Result” of ABS actuator and electric unit (control unit) with CONSULT-III. Refer to
BRC-40, "
CONSULT-III Function".
Is any DTC detected?
YES >> Repair or replace the malfunctioning part.
NO >> Replace BCM. Refer to BCS-81, "
Removal and Installation".
DTC CONSULT-III display
description DTC Detection Condition Probable cause
U0415 VEHICLE SPEED When the vehicle speed signal received from
the ABS actuator and elec
tric unit (control
unit) remains abnormal for 2 seconds or more.  ABS actuator and electric unit (control unit)
BCM
Revision: 2010 May2011 QX56

BRAKE FLUIDBR-11
< PERIODIC MAINTENANCE >
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NOTE:
Since brake fluid is conveyed by the motor, the brake pedal is not necessarily depressed.
RefillingINFOID:0000000006222465
FRONT BRAKE
CAUTION:
 If the brake fluid adheres to the brake caliper assembly and disc rotor, quickly wipe it off.
 Never spill or splash brake fluid on painted surfaces. Brake fluid may seriously damage paint. Wipe it
off immediately and wash with wate r if it gets on a painted surface.
 Never operate the brake pedal with the reservoir cap removed. Failure to do this may cause the scat-
tering of brake fluid.
 Never operate the brake pedal excessively during the work procedure.
 Monitor the fluid level in the reservoir tank while performing the refilling.
1. Check that there is no foreign material in t he reservoir tank, and refill with new brake fluid.
CAUTION:
 Never reuse drained brake fluid.
 Never allow oils other than brake fl uid to enter the reservoir tank.
2. Turn the ignition switch ON.
3. Connect a vinyl tube to the bleed valve.
4. Depress the brake pedal and loosen the bleeder valve.
5. Depress the brake pedal several times until the re filled brake fluid is discharged and tighten the air
bleeder to the specified torque with the brake pedal depressed. Refer to BR-36, "
BRAKE CALIPER
ASSEMBLY : Exploded View".
6. Perform the air bleeding. Refer to BR-11, "
Bleeding Brake System".
REAR BRAKE
CAUTION:
 If the brake fluid adheres to the brake caliper assembly and disc rotor, quickly wipe it off.
 Never spill or splash brake fluid on painted surfaces. Brake fluid may seriously damage paint. Wipe it
off immediately and wash with wate r if it gets on a painted surface.
 Never operate the brake pedal with the reservoir cap removed. Failure to do this may cause the scat-
tering of brake fluid.
 Never operate the brake pedal excessively during the work procedure.
 Monitor the fluid level in the reservoir tank while performing the refilling.
1. Check that there is no foreign material in t he reservoir tank, and refill with new brake fluid.
CAUTION:
 Never reuse drained brake fluid.
 Never allow oils other than brake fl uid to enter the reservoir tank.
2. Turn the ignition switch ON.
3. Connect a vinyl tube to the bleed valve.
4. Depress the brake pedal and loosen the bleeder valve.
5. Depress the brake pedal several times until the re filled brake fluid is discharged and tighten the air
bleeder to the specified torque with the brake pedal depressed. Refer to BR-42, "
BRAKE CALIPER
ASSEMBLY : Exploded View".
NOTE:
Since brake fluid is conveyed by the motor, the brake pedal is not necessarily depressed.
6. Perform the air bleeding. Refer to BR-11, "
Bleeding Brake System".
Bleeding Brake SystemINFOID:0000000006222466
CAUTION:
 Bleed air in the following order: motor/accumulator assembly → front right brake → front left brake
→ rear left brake → and rear right brake.
 The VDC warning lamp, ABS warning lamp and br ake warning lamp turn ON and DTC “C118E” may
be detected in self-diagnosis result for “ABS” with CONSULT-III when the brake pedal is excessively
operated, such as air bleeding. This is not a system malfunction because this occurs due to the tem-
porary decrease in accumulator fl uid pressure. The system returns to normal condition when the
accumulator fluid pressure reaches the specified pressu re with the ignition switch ON and the VDC
Revision: 2010 May2011 QX56

BR-12
< PERIODIC MAINTENANCE >
BRAKE FLUID
warning lamp, ABS warning lamp, and brake warning lamp turn OFF. After these steps, erase self-
diagnosis results for “ABS” with CONSULT-III.
- DTC other than “C118E” is detected: Refer to BRC-51, "
DTC Index".
NOTE:
When the ignition switch is ON, the brake warning la mp may turns ON even when the parking brake pedal is
released with the brake fluid within the specified level. This indicates the decrease in accumulator fluid pres-
sure.
MOTOR/ACCUMULATOR ASSEMBLY
CAUTION:
 If the brake fluid adheres to the brake caliper assembly and disc rotor, quickly wipe it off.
 Never spill or splash brake fluid on painted surfaces. Brake fluid may seriously damage paint. Wipe it
off immediately and wash with wate r if it gets on a painted surface.
 Never operate the brake pedal with the reservoir cap removed. Failure to do this may cause the scat-
tering of brake fluid.
 Never operate the brake pedal excessively during the work procedure.
 Monitor the fluid level in the reservoir tank while performing the air bleeding.
 Bleed air in the following order: motor/accumulator assembly → front right brake → front left brake
→ rear left brake → and rear right brake.
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more.
3. Check that there is no foreign material in the reservoir tank, and refill with new brake fluid. CAUTION:
 Never reuse drained brake fluid.
 Never allow oils other than brake fluid to enter the reservoir tank.
4. Turn the ignition switch ON. NOTE:
The motor is activated and automatically stops.
5. Turn the ignition switch OFF.
6. Depress the brake pedal 20 times or more. NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
7. Repeat steps 4 to 6 for 5 times.
8. Turn the ignition switch ON to check that the time between motor activation and automatic stop is less
than 18 seconds. If the time is 18 seconds or more, repeat from Step 4 to 8.
FRONT BRAKE
CAUTION:
 If the brake fluid adheres to the brake caliper assembly and disc rotor, quickly wipe it off.
 Never spill or splash brake fluid on painted surfaces. Brake fluid may seriously damage paint. Wipe it
off immediately and wash with wate r if it gets on a painted surface.
 Never operate the brake pedal with the reservoir cap removed. Failure to do this may cause the scat- tering of brake fluid.
 Never operate the brake pedal excessively during the work procedure.
 Monitor the fluid level in the reservoir tank while performing the air bleeding.
 Bleed air in the following order: motor/accumulator assembly → front right brake → front left brake
→ rear left brake → and rear right brake.
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more. NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
3. Check that there is no foreign material in the reservoir tank, and refill with new brake fluid. CAUTION:
 Never reuse drained brake fluid.
 Never allow oils other than brake fluid to enter the reservoir tank.
4. Turn the ignition switch ON.
Revision: 2010 May2011 QX56

HYDRAULIC BOOSTER ASSEMBLYBR-15
< PERIODIC MAINTENANCE >
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HYDRAULIC BOOSTER ASSEMBLY
InspectionINFOID:0000000006222467
OPERATION CHECK
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more. NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
3. Check that the fluid level in the reservoir tank is MAX line.
4. Position the selector lever in P range to release the parking brake.
5. Turn the ignition switch ON to check the time between motor activation and motor stop.
6. After the motor is stopped, check that the ABS warning lamp and the VDC warning lamp in the combina- tion meter are OFF when the engine is started.
7. Stop the engine (ignition switch OFF).
8. Turn the ignition switch ON and depress the brake pedal 4 to 5 times to check the time between motor activation and motor stop.
9. Turn the ignition switch OFF. Turn the ignition switch ON again. Check that the VDC warning lamp turns ON when the brake pedal is depressed 15 to 20 times.
10. Check that the VDC warning lamp turns ON when the brake pedal is depressed 15 to 20 times after the lapse of 120 seconds or more after the ignition switch is turned ON again.
11. Perform the self-diagnosis for “ABS” with CONSULT-III and erase self-diagnosis results.
FUNCTION CHECK
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more.
NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
3. Turn the ignition switch ON with the brake pedal depr essed to check that the clearance between the brake
pedal and the dash lower panel decreases. Motor operating time : 18 seconds or less
Motor operating time : 2
− 11 seconds
Revision: 2010 May2011 QX56

HYDRAULIC BOOSTER ASSEMBLYBR-29
< REMOVAL AND INSTALLATION >
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Removal and InstallationINFOID:0000000006222484
REMOVAL
1. Turn the ignition switch OFF. CAUTION:
Never turn the ignition switch ON before th e completion of the installation procedure.
2. Drain brake fluid. Refer to BR-10, "
Draining".
3. Depress the brake pedal 20 times or more to release the pressure from the accumulator. CAUTION:
Always perform this step before re moving the hydraulic booster assembly.
4. Disconnect hydraulic booster assembly harness connector.
5. Separate the brake tube from hydraulic booste r assembly with a flare nut wrench. Refer to BR-22,
"FRONT : Exploded View".
6. Remove brake tube from clip.
1. Reservoir cap 2. Lab el 3. Reservoir tank
4. Pin 5. Motor/accumulator assembly 6. Brake tube
7. Brake hose assembly 8. Grommet 9. Harness band
10. Collar 11. Bushing 12. Pin mount
13. Grommet 14. Bracket 15. Cap
16. Bushing 17. Bracket 18. ABS actuator and electric unit (con- trol unit)
19. Gasket 20. Spacer
: Apply brake fluid.
Refer to GI-4, "
Components" for symbols not described on the above.
JPFIA0748GB
Revision: 2010 May2011 QX56

HYDRAULIC BOOSTER ASSEMBLYBR-31
< REMOVAL AND INSTALLATION >
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2. Remove the reservoir tank mounting pin with a pin punch (com- mercial service tool).
3. Remove bolt and remove the reservoir tank and grommets from the ABS actuator and electric unit (control unit).
CAUTION:
Never drop the removed parts. The parts must not be
reused if they are dropped.
4. Slide the clamp and remove brake hose assembly.
5. Remove the brake tube with a flare nut wrench. CAUTION:
Never scratch the flare nut and the brake tube.
6. Remove the cap with a suitable tool (A).
7. Remove grommets and screws ( ) and remove motor/accumu- lator assembly harness.
8. Cut harness band. CAUTION:
Never damage the harness.
9. Remove motor/accumulator assembly from ABS actuator and electric unit (control unit).
10. Remove bushings and collars from motor/accumulator assem- bly.
11. Remove brackets and bushing fr om ABS actuator and electric
unit (control unit).
12. Remove pin mount.
13. After replacing motor/accumulator assembly, always follow the accumulator disposal procedure to discard the motor/accumulator assembly. Refer to BR-33, "
Disposal".
ASSEMBLY
Note the following, and assembly in the reverse order of disassembly.
 Never use mineral oils such as kerosene or gasoline and rubber grease during the cleaning and assembly
process.
 Never drop the removed parts when installing. The parts must not be reused if they are dropped.
 Never allow foreign matter (e.g. dust) and oils ot her than brake fluid to enter the reservoir tank.
 For non reusable parts, refer to BR-28, "
Exploded View".
 When connecting motor/accumulator assembly harness, check the order of harness colors.
 Temporarily tighten the brake tube flare nut to the motor/accumula- tor assembly and ABS actuator and electric unit (control unit) by
hand. Then tighten it to the specified torque with a crowfoot and
torque wrench.
CAUTION:
Never scratch the flare nut and the brake tube.
JPFIA0750ZZ
JPFIA0752ZZ
JPFIA0751ZZ
A: Black
B: Red
JPFIA0753ZZ
Revision: 2010 May2011 QX56

BR-32
< REMOVAL AND INSTALLATION >
HYDRAULIC BOOSTER ASSEMBLY
 Apply new brake fluid to grommet of between reservoir tank and grommet and ABS actuator and electric unit
(control unit).
Inspection and AdjustmentINFOID:0000000006222486
ADJUSTMENT BEFORE INSTALLATION
Input Rod Length adjustment
1. Loosen the lock nut (1) and adjust the input rod (2) to the speci-
fied length (A).
2. Tighten the lock nut to the specified torque.
INSPECTION AFTER INSTALLATION
Operation Check
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more. NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
3. Check that the fluid level in the reservoir tank is MAX line.
4. Position the selector lever in P range to release the parking brake.
5. Turn the ignition switch ON to check the time between motor activation and motor stop.
6. After the motor is stopped, check that the ABS warn ing lamp and the VDC warning lamp in the combina-
tion meter are OFF when the engine is started.
7. Stop the engine (ignition switch OFF).
8. Turn the ignition switch ON and depress the brake pedal 4 to 5 times to check the time between motor activation and motor stop.
9. Turn the ignition switch OFF. Turn the ignition swit ch ON again. Check that the VDC warning lamp turns
ON when the brake pedal is depressed 15 to 20 times.
10. Check that the VDC warning lamp turns ON when the brake pedal is depressed 15 to 20 times after the lapse of 120 seconds or more after the ignition switch is turned ON again.
11. Perform the self-diagnosis for “ABS” with CONSULT- III and erase all the stored self-diagnosis results.
Function Check
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more.
NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
3. Turn the ignition switch ON with the brake pedal depr essed to check that the clearance between the brake
pedal and the dash lower panel decreases. A : Refer to
BR-47, "
Brake Booster".
JPFIA0728ZZ
Motor operating time : 18 seconds or less
Motor operating time : 2 − 11 seconds
Revision: 2010 May2011 QX56