2006 INFINITI QX56 stop start

BRC-8
[VDC/TCS/ABS]
SYSTEM DESCRIPTION
Revision: November 20092006 QX56
ABS FunctionEFS004XC

The Anti-Lock Brake System detects wheel revolution while braking and improves handling stability during
sudden braking by electrically preventing wheel lockup. Maneuverability is also improved for avoiding
obstacles.

If the electrical system malfunctions, the Fail-Safe function is activated, the ABS becomes inoperative and
the ABS warning lamp turns on.

The electrical system can be diagnosed using CONSULT-II.

During ABS operation, the brake pedal may vibrate lightly and a mechanical noise may be heard. This is
normal.

Just after starting the vehicle, the brake pedal may vibrate or a motor operating noise may be heard from
engine compartment. This is a normal status of operation check.

Stopping distance may be longer than that of vehicles without ABS when vehicle drives on rough, gravel,
or snow-covered (fresh, deep snow) roads.
EBD FunctionEFS004XD

Electronic Brake Distribution is a function that detects subtle slippages between the front and rear wheels
during braking, and it improves handling stability by electronically controlling the brake fluid pressure
which results in reduced rear wheel slippage.

If the electrical system malfunctions, the Fail-Safe function is activated, the EBD and ABS become inoper-
ative, and the ABS warning lamp and BRAKE warning lamp are turned on.

The electrical system can be diagnosed using CONSULT-II.

During EBD operation, the brake pedal may vibrate lightly and a mechanical noise may be heard. This is
normal.

Just after starting the vehicle, the brake pedal may vibrate or a motor operating noise may be heard from
engine compartment. This is a normal status of operation check.
TCS FunctionEFS004XE

Spinning of the drive wheels is detected by the ABS actuator and electric unit (control unit) using inputs
from the wheel speed sensors. If wheel spin occurs, the drive wheel right and left brake fluid pressure
control and engine fuel cut are activated while the throttle value is restricted to reduce the engine torque
and decrease the amount of wheel spin. In addition, the throttle opening is controlled to achieve the opti-
mum engine torque.

Depending on road condition, the vehicle may have a sluggish feel. This is normal, because optimum trac-
tion has the highest priority during TCS operation.

TCS may be activated during sudden vehicle acceleration, wide open throttle acceleration, sudden trans-
mission shifts or when the vehicle is driven on a road with a varying surface friction coefficient.

The SLIP indicator lamp flashes to inform the driver of TCS operation.
VDC FunctionEFS004XF

In addition to the ABS/TCS function, the driver steering amount and brake operation amount are detected
from the steering angle sensor and front and rear pressure sensors, and the vehicle's driving status
(amount of under steering/over steering) is determined using inputs from the yaw rate sensor/side G sen-
sor, wheel speed sensors, etc. and this information is used to improve vehicle stability by controlling the
braking and engine torque application to the wheels.

The SLIP indicator lamp flashes to inform the driver of VDC operation.

During VDC operation, the vehicle body and brake pedal may vibrate lightly and a mechanical noise may
be heard. This is normal.

The ABS warning lamp, VDC OFF indicator lamp and SLIP indicator lamp may turn on when the vehicle is
subject to strong shaking or large vibration, such as when the vehicle is on a turn table or a ship while the
engine is running or on a steep slope. In this case, restart the engine on a normal road and if the ABS
warning lamp, VDC OFF indicator lamp and SLIP indicator lamp turn off, there is no problem.
Fail-Safe FunctionEFS004XG
CAUTION:
If the Fail-Safe function is activated, perform the Self Diagnosis for ABS/TCS/VDC system.

TROUBLE DIAGNOSISBRC-29
[VDC/TCS/ABS]
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Revision: November 2009 2006 QX56
6. Select the required diagnostic location from the “SELECT DIAG
MODE ” screen.
For further information, see the CONSULT-II Operation Manual.
SELF-DIAGNOSIS
Description
If an error is detected in the system, the ABS warning lamp will turn on. In this case, perform self-diagnosis as
follows:
Operation Procedure
1. Turn ignition switch OFF.
2. Connect CONSULT-II and CONSULT-II CONVERTER to the data link connector.
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
3. Turn ignition switch ON.
4. Start engine and drive at approximately 30 km/h (19 MPH) or more for approximately 1 minute.
5. After stopping the vehicle, with the engine running, touch “START (NISSAN BASED VHCL)”, “ABS ”,
“SELF-DIAG RESULTS ” in order on the CONSULT-II screen.
CAUTION:
If “START (NISSAN BASED VHCL)” is touched immediately after starting the engine or turning on
the ignition switch, “ABS” might not be displayed in the SELECT SYSTEM screen. In this case,
repeat the operation from step 1.
6. The self-diagnostic results are displayed. (If necessary, the self-diagnostic results can be printed out by touching “PRINT”.)

When “NO DTC IS DETECTED ” is displayed, check the ABS warning lamp, SLIP indicator lamp and
VDC OFF indicator lamp.
7. Conduct the appropriate inspection from the display item list, and repair or replace the malfunctioning component.
8. Start engine and drive at approximately 30 km/h (19 MPH) or more for approximately 1 minute. CAUTION:

When a wheel sensor “short-circuit” is detected, if the vehicle is not driven at 30 km/h (19 MPH)
for at least 1 minute, the ABS warning lamp will not turn off even if the malfunction is repaired.
9. Turn ignition switch OFF to prepare for erasing the memory.
10. Start the engine and touch “START (NISSAN BASED VHCL)”, “ABS”, “SELF-DIAG RESULTS”, “ERASE”
in order on the CONSULT-II screen to erase the error memory.
If “ABS” is not indicated, go to GI-40, "
CONSULT-II Data Link Connector (DLC) Circuit" .
CAUTION:
If the error memory is not erased, re-conduct the operation from step 5.
11. For the final inspection, drive at approximately 30 km/h (19 MPH) or more for approximately 1 minute and confirm that the ABS warning lamp, SLIP indicator lamp, and VDC OFF indicator lamp are off.
BCIA0031E

TROUBLE DIAGNOSISBRC-33
[VDC/TCS/ABS]
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Revision: November 2009 2006 QX56
CAUTION:
When “START (NISSAN BASED VHCL)” is touched immediately after starting the engine or turning
on the ignition switch, “ABS” might not be displayed in the SELECT SYSTEM screen. In this case,
repeat the operation from step 2.
3. Return to the SELECT MONITOR ITEM screen, and touch “ECU INPUT SIGNALS”, “MAIN SIGNALS ”, or
“SELECTION FROM MENU ”. Refer to the following information.
4. When “START” is touched, the data monitor screen is displayed.
Display Item List
Item
(Unit) Data monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELECTION
FROM MENU
GEAR ××× Gear position judged by PNP
switch signal is displayed.
FR RH SENSOR
(km/h, MPH) ××× Wheel speed calculated by front
RH wheel sensor signal is dis-
played.
FR LH SENSOR
(km/h, MPH) ××× Wheel speed calculated by front LH
wheel sensor signal is displayed.
RR RH SENSOR
(km/h, MPH) ××× Wheel speed calculated by rear RH
wheel sensor signal is displayed.
RR LH SENSOR
(km/h, MPH) ×××
Wheel speed calculated by rear LH
wheel sensor signal is displayed.
BATTERY VOLT
(V) ××× Voltage supplied to ABS actuator
and electric unit (control unit) is dis-
played.
N POSI SIG ––× Shift position judged by PNP switch
signal.
P POSI SIG ––× Shift position judged by PNP switch
signal.
ACCEL POS SIG
(%) ×
–×Throttle valve open/close status
judged by CAN communication sig-
nal is displayed.
ENGINE SPEED
(rpm) ××× Engine speed judged by CAN com-
munication signal is displayed.
STR ANGLE SIG
(deg) ×
–×Steering angle detected by steering
angle sensor is displayed.
YAW R AT E S E N
(d/s) ×××
Yaw rate detected by yaw rate sen-
sor is displayed.
DECEL G-SEN
(d/s) ××× Longitudinal acceleration detected
by decel G-sensor is displayed.
SIDE G-SENSOR
(m/s
2 ) ×
– × Transverse acceleration detected
by side G-sensor is displayed.
STOP LAMP SW
(ON/OFF) ××× Stop lamp switch (ON/OFF) status
is displayed.
OFF SW
(ON/OFF)
×× × VDC OFF switch (ON/OFF) status
is displayed.
ABS WARN LAMP
(ON/OFF) –
×× ABS warning lamp (ON/OFF) status
is displayed.
SLIP LAMP
(ON/OFF) –
×× SLIP indicator lamp (ON/OFF) sta-
tus is displayed.
FR LH IN SOL
(ON/OFF) –
×× Front LH IN ABS solenoid (ON/
OFF) status is displayed.
FR LH OUT SOL
(ON/OFF) –
×× Front LH OUT ABS solenoid (ON/
OFF) status is displayed.

TROUBLE DIAGNOSISBRC-35
[VDC/TCS/ABS]
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Revision: November 2009 2006 QX56
×: Applicable
– : Not applicable
ACTIVE TEST
CAUTION:

Do not perform active test while driving.

Make sure to completely bleed air from the brake system.

The ABS and brake (EBD) warning lamps turn on during the active test.
R POSI SIG ––× Shift position judged by PNP switch
signal.
4WD FAIL REQ ––× The state of 4WD controller is dis-
played by CAN communication sig-
nal.
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)
status is displayed.
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 dis-
played.
RELEASE SW NO ––× Release switch signal (ON/OFF)
status is displayed. "ON" indicates
that the brake pedal is depressed.
"OFF" is that the brake pedal is
released.
RELEASE SW NC ––× Release switch signal (ON/OFF)
status is displayed. "OFF" indi-
cates that the brake pedal is
depressed on. "ON" is that the
brake pedal is released.
OHB FAIL ––× OHB fail status is displayed.
HBA FAIL ––× HBA fail status is displayed.
OHB SIG ––× OHB operation (ON/OFF) status is
displayed.
HBA SIG ––× HBA operation (ON/OFF) status is
displayed.
PRES CTRL ACC ––× Pressure control state (ON/OFF) is
displayed. It is applied only to an
ICC vehicle.
PRES FAIL ACC ––× Pressure control fail state (ON/
OFF) is displayed. It is applied only
to an ICC vehicle.
STP OFF RLY ––× Stop lamp relay signal (ON/OFF)
status is displayed.
Item
(Unit) Data monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELECTION
FROM MENU

BRC-36
[VDC/TCS/ABS]
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
Operation Procedure
1. Connect the CONSULT-II and CONSULT-II CONVERTER to the data link connector and start the engine.
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
2. Touch “START (NISSAN BASED VHCL) ” on the display screen.
3. Touch “ABS”.
If “ABS” is not indicated, go to GI-40, "
CONSULT-II Data Link Connector (DLC) Circuit" .
4. Touch “ACTIVE TEST”.
5. The SELECT TEST ITEM screen is displayed.
6. Touch necessary test item.
7. With the “MAIN SIGNALS ” display selected, touch “START”.
8. The Active Test screen will be displayed, so conduct the following test.
Solenoid Valve Operation Chart
*: ON for 1 to 2 seconds after the touch, and then OFF
NOTE:

If active test is performed with brake pedal depressed, pedal stroke may change. This is normal.

“TEST IS STOPPED ” is displayed approximately 10 seconds after operation starts.

After “TEST IS STOPPED ” is displayed, to perform test again, repeat Step 6.
LBR379
Operation ABS solenoid valve ABS solenoid valve (ACT)
UP KEEP DOWN UP ACTUA-
TOR UP ACTUA-
TOR KEEP
FR RH SOL
FR RH ABS SOLE-
NOID (ACT) FR RH IN SOL
OFF ON ON OFF OFF OFF
FR RH OUT SOL OFF OFF ON* OFF OFF OFF
FR LH SOL
FR LH ABS SOLE-
NOID (ACT) FR LH IN SOL
OFF ON ON OFF OFF OFF
FR LH OUT SOL OFF OFF ON* OFF OFF OFF
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

TROUBLE DIAGNOSISBRC-37
[VDC/TCS/ABS]
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Revision: November 2009 2006 QX56
ABS Motor
Touch “ON” and “OFF ” on the screen. Check that ABS motor relay
operates as shown in table below.
NOTE:

If active test is performed with brake pedal depressed, pedal
stroke may change. This is normal.

“TEST IS STOPPED ” is displayed approximately 10 seconds
after operation starts.
Booster Drive
CAUTION:
Perform active test subject to the conditions below.

Do not operate brake pedal during active test.

Make sure the engine revolution is over 500 rpm.

Make sure the vehicle is not moving.
Touch "UP" and "DOWN" on the screen. Check that booster drive
operates as shown in table below.
NOTE:
"TEST IS STOPPED" is displayed approximately 10 seconds after operation starts.
Operation ONOFF
ABS actuator relay ONON
ABS motor relay ONOFF
SFIA0593E
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
WFIA0350E

TROUBLE DIAGNOSES FOR SYMPTOMSBRC-59
[VDC/TCS/ABS]
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Revision: November 2009 2006 QX56
Long Stopping DistanceEFS004YB
1. CHECK BASE BRAKING SYSTEM PERFORMANCE
1. Disable ABS by disconnecting ABS actuator and electric unit (control unit) connector.
2. Drive vehicle and check brake operation. NOTE:

Stopping distance may be longer than vehicles without ABS when road condition is slippery.

Driving the vehicle with the ABS actuator and electric unit (control unit) disconnected may induce DTCs
in electrical control units using CAN communication. After the inspection, clear all DTCs. Refer to BRC-
10, "CAN COMMUNICATION" .
OK or NG
OK >> Go to BRC-57, "ABS Works Frequently" .
NG >> Perform Basic Inspection. Refer to BRC-23, "
Basic Inspection" .
ABS Does Not WorkEFS004YC
CAUTION:
The ABS does not operate when the vehicle speed is 10 km/h (6 MPH) or less.
1. CHECK WARNING LAMP ACTIVATION
Turn ignition switch ON and check for warning lamp activation.

Warning lamp should activate for approximately 2 seconds after turning the ignition switch ON.
OK or NG
OK >> Carry out self-diagnosis. Refer to BRC-29, "SELF-DIAGNOSIS" .
NG >> Go to BRC-60, "
ABS Warning Lamp Does Not Come On When Ignition Switch Is Turned On" .
Pedal Vibration or ABS Operation NoiseEFS004YD
NOTE:
During ABS activation, pedal vibration may be felt and a noise may be heard. This is normal and does not indi-
cate a malfunction.
1. CHECK SYMPTOM
1. Apply brake.
2. Start engine.
Does the symptom occur only when engine is started?
YES >> Carry out self-diagnosis. Refer to BRC-29, "SELF-DIAGNOSIS" .
NO >> GO TO 2.
2. RECHECK SYMPTOM
Does the symptom occur only when electrical equipment switches (such as headlamps) are turned on?
YES >> Check for radio, antenna or related wiring that is routed too close to the ABS actuator and electric unit (control unit) and reroute as necessary.
NO >> Go to BRC-57, "
ABS Works Frequently" .

BRC-62
[VDC/TCS/ABS]
ON-VEHICLE SERVICE
Revision: November 20092006 QX56
ON-VEHICLE SERVICEPFP:00000
Adjustment of Steering Angle Sensor Neutral PositionEFS004YH
After removing/installing or replacing ABS actuator and electric unit (control unit), steering angle sensor, steer-
ing and suspension components which affect wheel alignment or after adjusting wheel alignment, be sure to
adjust neutral position of steering angle sensor before running vehicle.
NOTE:
Adjustment of steering angle sensor neutral position requires CONSULT-II.
1. Stop vehicle with front wheels in straight-ahead position.
2. Connect CONSULT-II and CONSULT-II CONVERTER to data
link connector on vehicle, and turn ignition switch ON (do not
start engine).
3. Touch “ABS”, “WORK SUPPORT ” and “ST ANGLE SENSOR
ADJUSTMENT ” on CONSULT-II screen in this order.
4. Touch “START”.
CAUTION:
Do not touch steering wheel while adjusting steering angle
sensor.
5. After approximately 10 seconds, touch “END”. (After approxi-
mately 60 seconds, it ends automatically.)
6. Turn ignition switch OFF, then turn it ON again.
7. Run vehicle with front wheels in straight-ahead position, then stop.
8. Select “DATA MONITOR ”, “SELECTION FROM MENU ”, and
“STR ANGLE SIG ” on CONSULT-II screen. Then check that
“STR ANGLE SIG ” is within 0±3.5 deg. If value is more than specification, repeat steps 1 to 5.
9. Erase memory of ABS actuator and electric unit (control unit) and ECM.
10. Turn ignition switch to OFF.
Calibration of Decel G SensorEFS004YI
After removing/installing or replacing ABS actuator and electric unit (control unit), yaw rate/side/decel G sen-
sor, steering and suspension components which affect wheel alignment or after adjusting wheel alignment, be
sure to calibrate the decel G sensor before running vehicle.
NOTE:
Calibration of decel G sensor requires CONSULT-II.
1. Stop vehicle with front wheels in straight-ahead position. CAUTION:

The work should be done on a level area with an unloaded vehicle.

Keep all the tires inflated to the correct pressures. Adjust the tire pressure to the specified pres-
sure value.
2. Connect CONSULT-II with CONSULT-II CONVERTER to data link connector on vehicle, and turn ignition switch ON (do not start engine).
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
3. Touch "ABS", "WORK SUPPORT" and "DECEL G SEN CALIBRATION" on CONSULT-II screen in this order. Refer to BRC-28, "
CONSULT-II BASIC OPERATION PROCEDURE" .
BBIA0369E
WFIA0239E