warning INFINITI QX56 2011 Factory Repair Manual

DIAGNOSIS SYSTEM [ABS ACTUATOR AND ELECTRIC UNIT (CONTROL
UNIT)]
BRC-43
< SYSTEM DESCRIPTION > [WITH VDC]
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from ABS actuator and electric unit (control unit) on the vehi cle, a drive signal is sent to the actuator to check
its operation.
CAUTION:
 Never perform ACTIVE TEST while driving the vehicle.
 Always bleed air from brake system before active test.
 Never perform active test when system is malfunctioning.
NOTE:
 When active test is performed while depressing the pedal, the pedal depressing stroke may change. This is
not a malfunction.
 “TEST IS STOPPED” is displayed approx. 10 seconds after operation start.
 When performing active test again after “TEST IS STOPPED” is displayed, select “BACK”.
 ABS warning lamp, brake warning lamp and VDC warning lamp may turn ON during active test. This is not a malfunction.
ABS IN Valve and ABS OUT Valve
When “Up”, “Keep” or “Down” is selected on display scr een, the following items are displayed when system is
normal.
*: Immediately after being selected, status is “O n”. Status changes to “Off” after approx. 2 seconds.
ABS IN Valve (ACT) and ABS OUT Valve (ACT)
When “Up”, “ACT KEEP” or “ACT UP” is selected on display screen, the following items are displayed when
system is normal.
Test item Display Item Display
Up Keep Down
FR RH SOL FR RH IN SOL Off On* On*
FR RH OUT SOL Off Off On*
FR LH SOL FRLH IN SOL Off On* On*
FR LH OUT SOL Off Off On*
RR RH SOL RR RH IN SOL Off On* On*
RR RH OUT SOL Off Off On*
RR LH SOL RR LH IN SOL Off On* On*
RR LH OUT SOL Off Off On*
Test item Display Item Display
Up ACT KEEP ACT UP
FR RH SOL (ACT) FR RH IN SOL Off Off On*
FR RH OUT SOL Off Off Off
CV1 Off On* On*
SV1 Off Off On*
FR LH SOL (ACT) FR LH IN SOL Off Off On*
FR LH OUT SOL Off Off Off
CV1 Off On* On*
SV1 Off Off On*
RR RH SOL (ACT) RR RH IN SOL Off Off On*
RR RH OUT SOL Off Off Off
CV2 Off On* On*
SV2 Off Off On*
RR LH SOL (ACT) RR LH IN SOL Off Off On*
RR LH OUT SOL Off Off Off
CV2 Off On* On*
SV2 Off Off On*
Revision: 2010 May2011 QX56

ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)BRC-45
< ECU DIAGNOSIS INFORMATION > [WITH VDC]
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ECU DIAGNOSIS INFORMATION
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Reference ValueINFOID:0000000006222579
CONSULT-III DATA MONITOR STANDARD VALUE
Monitor item Condition Reference values in normal operation
FR LH SENSOR Vehicle stopped 0.00 km/h (MPH)
When driving
(Note 1)Nearly matches the speedometer dis-
play (within
±10%)
FR RH SENSOR Vehicle stopped 0.00 km/h (MPH)
When driving
(Note 1)Nearly matches the speedometer dis-
play (within
±10%)
RR LH SENSOR Vehicle stopped 0.00 km/h (MPH)
When driving
(Note 1)Nearly matches the speedometer dis-
play (within
±10%)
RR RH SENSOR Vehicle stopped 0.00 km/h (MPH)
When driving
(Note 1)Nearly matches the speedometer dis-
play (within
±10%)
DECEL G-SEN When stopped Approx. 0 G
During acceleration Positive value
During deceleration Negative value
FR RH IN SOL Active On
Inactive Off
FR RH OUT SOL Active On
Inactive Off
FR LH IN SOL Active On
Inactive Off
FR LH OUT SOL Active On
Inactive Off
RR RH IN SOL Active On
Inactive Off
RR RH OUT SOL Active On
Inactive Off
RR LH IN SOL Active On
Inactive Off
RR LH OUT SOL Active On
Inactive Off
EBD WARN LAMP When brake warning lamp is ON
(Note 2)On
When brake warning lamp is OFF
(Note 2)Off
STOP LAMP SW Brake pedal depressed On
Brake pedal not depressed Off
MOTOR RELAY Active On
Inactive Off
ACTUATOR RLY Active On
Inactive (in fail-safe mode) Off
Revision: 2010 May2011 QX56

BRC-46
< ECU DIAGNOSIS INFORMATION >[WITH VDC]
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
ABS WARN LAMPWhen ABS warning lamp is ON
(Note 2)On
When ABS warning lamp is OFF
(Note 2)Off
OFF LAMP When VDC OFF indicator lamp is ON
(Note 2)On
When VDC OFF indicator lamp is OFF
(Note 2)Off
OFF SW VDC OFF switch ON On
VDC OFF switch OFF Off
SLIP/VDC LAMP When VDC warning lamp is ON or Blinking
(Note 2)On
When VDC warning lamp is OFF
(Note 2)Off
BATTERY VOLT Ignition switch ON 10 – 16 V
GEAR Driving 1 – 7
Depending on shift status
ENGINE SPEED Engine stopped 0 tr/min
Engine running Almost same reading as tachometer
YAW RATE SEN Vehicle stopped Approx. 0 d/s
Turning right Negative value
Turning left Positive value
R POSI SIG When selector lever is in the R position On
When selector lever is in the other position than R Off
4WD MODE MON
(Note 3)
When 4WD sift switch is AUTO position AUTO
When 4WD sift switch is 4H position LOCK
When 4WD sift switch is 4L position ##
N POSI SIG When selector lever is in the N position On
When selector lever is in the other position than N Off
CV1 Active On
Inactive Off
CV2 Active On
Inactive Off
SV1 Active On
Inactive Off
SV2 Active On
Inactive Off
STOP LAMP SW2 Brake pedal depressed On
Brake pedal not depressed Off
ACCEL POS SIG Never depress accelerator pedal
(with ignition switch ON)
0%
Depress accelerator pedal
(with ignition switch ON) 0 – 100%
SIDE G-SENSOR Vehicle stopped
Approx. 0 m/s
2
Right turn Negative value
Left turn Positive value
STR ANGLE SIG When driving straight 0
±2.5 °
When steering wheel is steered to LH by 90 °Approx. +90 °
When steering wheel is steered to RH by 90 °Approx. –90 °
Monitor item Condition Reference values in normal operation
Revision: 2010 May2011 QX56

ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)BRC-47
< ECU DIAGNOSIS INFORMATION > [WITH VDC]
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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

BRC-48
< ECU DIAGNOSIS INFORMATION >[WITH VDC]
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
VDC function, TCS function, hill start assist function and
brake limited slip differential (BLSD) function. How-
ever, ABS function and EBD function are operated normally.
ABS FUNCTION
ABS warning lamp and VDC warning lamp in combinati on meter turn ON when a malfunction occurs in system
[ABS actuator and electric unit (control unit)]. The c ontrol is suspended for VDC function, TCS function, ABS
function, hill start assist function and brake limited sl ip differential (BLSD) function. The vehicle status
becomes the same as models without VDC function, TCS f unction, ABS function, hill start assist function and
brake limited slip differential (BLSD) function. However, EBD function is operated normally.
NOTE:
ABS self-diagnosis sound may be heard the same as in the normal condition, because self-diagnosis is per-
formed when ignition switch turns ON and when vehicle initially starts.
EBD FUNCTION
ABS warning lamp, brake warning lamp and VDC warning lamp in combination meter turn ON when a mal-
function occurs in system [ABS actuator and electric unit (control unit)]. The control is suspended for VDC
function, TCS function, ABS function, EBD function, hill start assist function and brake limited slip differential
(BLSD) function. The vehicle status becomes the sa me as models without VDC function, TCS function, ABS
function, EBD function, hill star t assist function and brake limited slip differential (BLSD) function.
DTC Malfunction detected condition Fail-safe condition
C1101 When an open circuit is detected in rear RH wheel sensor circuit.
The following functions are sus-
pended.
 VDC function
 TCS function
 ABS function
 EBD function (only when both 2 rear wheels are malfunctioning)
 hill start assist function
 Brake limited slip differential (BLSD) function
C1102 When an open circuit is detected in rear LH wheel sensor circuit.
C1103 When an open circuit is detected in front RH wheel sensor circuit.
C1104 When an open circuit is detected in front LH wheel sensor circuit.
C1105
 When power supply voltage of rear RH wheel sensor is low.
 When distance between rear RH wheel sensor and rear RH wheel sensor rotor is
large.
 When installation of rear RH wheel sensor or rear RH wheel sensor rotor is not normal.
C1106  When power supply voltage of rear LH wheel sensor is low.
 When distance between rear LH wheel sensor and rear LH wheel sensor rotor is
large.
 When installation of rear LH wheel sensor or rear LH wheel sensor rotor is not nor-
mal.
C1107  When power supply voltage of front RH wheel sensor is low.
 When distance between front RH wheel sensor and front RH wheel sensor rotor
is large.
 When installation of front RH wheel sensor or front RH wheel sensor rotor is not normal.
C1108  When power supply voltage of front LH wheel sensor is low.
 When distance between front LH wheel sensor and front LH wheel sensor rotor is
large.
 When installation of front LH wheel sensor or front LH wheel sensor rotor is not normal.
C1109  When ignition voltage is 10 V or less.
 When ignition voltage is 16 V or more. The following functions are sus-
pended.
 VDC function
 TCS function
 ABS function
 EBD function
 hill start assist function
 Brake limited slip differential
(BLSD) function
C 1111
 When a malfunction is detected in motor or motor relay.
 When a low pressure malfunction is detected in accumulator.
 When a malfunction is detected in accumulator pressure sensor.
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

DIAGNOSIS AND REPAIR WORK FLOWBRC-61
< BASIC INSPECTION > [WITH VDC]
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YES >> GO TO 7.
NO >> Check harness and connectors based on the in formation obtained by interview. Refer to GI-40,
"Intermittent Incident".
7.FINAL CHECK
With CONSULT-III.
1. Check the reference value for “ABS”.
2. Recheck the symptom and check that the sympt om is not reproduced on the same conditions.
Is the symptom reproduced?
YES >> GO TO 3.
NO >> INSPECTION END
Diagnostic Work SheetINFOID:0000000006222586
Description
 In general, customers have their own criteria for a pr oblem. Therefore, it is important to understand the
symptom and status well enough by asking the customer about his/her concerns carefully. To systemize all
the information for the diagnosis, prepare the in terview sheet referring to the interview points.
 In some cases, multiple conditions that appear simultaneously may cause a DTC to be detected.
INTERVIEW SHEET SAMPLE
Interview sheet
Customer
name MR/MSRegistration
number
Initial year
registration
Vehicle type VIN
Storage date Engine Mileage km ( Mile)
Symptom †
Does not operate ( ) function
† Warning lamp for ( \
) turns ON.
† Noise † Vibration
† Other
( )
First occurrence † Recently † Other ( )
Frequency of occurrence † Always † Under a certain conditions of † Sometimes ( time(s)/day)
Climate con-
ditions †
Irrelevant
Weather † Fine † Cloud † Rain †Snow † Others ( )
Temperature † Hot †Warm † Cool † Cold † Temperature [Approx. °C ( °F)]
Relative humidity † High † Moderate † Low
Road conditions †
Urban area † Suburb area † Highway
† Mountainous road (uphill or downhill) †Rough road
Operating condition, etc. †
Irrelevant
† When engine starts † During idling
† During driving † During acceleration † At constant speed driving
† During deceleration
† During cornering (right curve or left curve)
† When steering wheel is steered (to right or to left)
Revision: 2010 May2011 QX56

C1118 TRANSFER CONTROL UNITBRC-87
< DTC/CIRCUIT DIAGNOSIS > [WITH VDC]
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C1118 TRANSFER CONTROL UNIT
DTC LogicINFOID:0000000006222607
DTC DETECTION LOGIC
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
“C 111 8” detected?
YES >> Proceed to diagnosis procedure. Refer to BRC-87, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222608
1.CHECK TRANSFER CO NTROL UNIT SYSTEM
With CONSULT-III.
Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is any DTC detected?
YES >> Check the DTC.
NO >> GO TO 2.
2.CHECK ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
With CONSULT-III.
1. Erase Self-diagnosis result for “ABS”.
2. Turn the ignition switch OFF.
3. Start the engine and drive the vehicle for a short period of time.
4. Check that the 4WD warning lamp turns OFF.
5. After the vehicle stops, perform self-diagnosis for “ABS”.
Is DTC
“C 111 8” detected?
YES >> Replace ABS actuator and electric unit (control unit). Refer to BRC-137, "Removal and Installa-
tion".
NO >> Check pin terminals and connection of each harness connector for abnormal conditions. Repair or
replace error-detected parts.
DTC Display Item Malfunction detected condition Possible causes
C1118 4WD SYSTEM When a malfunction is detected in transfer control unit
system.  Transfer control unit
 ABS actuator and electric unit
(control unit)
 CAN communication line
Revision: 2010 May2011 QX56

BRC-100
< DTC/CIRCUIT DIAGNOSIS >[WITH VDC]
C1145, C1146 YAW RATE/SIDE/DECEL G SENSOR
C1145, C1146 YAW RATE/SIDE/DECEL G SENSOR
DTC LogicINFOID:0000000006222623
DTC DETECTION LOGIC
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
“C1145” or “C1146” detected?
YES >> Proceed to diagnosis procedure. Refer to BRC-100, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222624
CAUTION:
 A malfunction in yaw rate/side/ decel G sensor system may be det ected when the vehicle sharply
turns during a spin turn, acceleratio n turn or drift driving while VDC function is OFF (VDC OFF indi-
cator lamp is in ON status). This is not a malfun ction if the status returns to normal after engine is
started again. In that case, erase self-diagn osis result memory using CONSULT-III.
 When the engine is in running stat us and the vehicle is on a turntable at the entrance of parking lot
or on a moving unit, VDC warning lamp may tu rn ON and “ABS” self-diagnosis may display “YAW
RATE SENSOR”. In this case, yaw rate sensor is not malfunctioning. The status returns to normal
when the vehicle is left from the turntable or movi ng unit and the engine is started again. In that
case, erase self-diagnosis result memory using CONSULT-III.
1.CHECK YAW RATE/SIDE/DECEL G SENSOR MOUNTING CONDITION
Check yaw rate/side/decel G sensor mounting condition. Refer to BRC-138, "
Exploded View".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace error-detected parts.
2.CHECK YAW RATE/SIDE/DECE L G SENSOR POWER SUPPLY
1. Turn the ignition switch OFF.
2. Disconnect yaw rate/side/decel G sensor harness connector.
3. Check voltage between yaw rate/side/dec el G sensor harness connector and ground.
4. Turn the ignition switch ON. CAUTION:
Never start engine.
5. Check voltage between yaw rate/side/dec el G sensor harness connector and ground.
DTC Display Item Malfunction detected condition Possible causes
C1145 YAW RATE SENSOR  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.  Harness or connector
 Yaw rate/side/decel G sensor
 ABS actuator and electric unit
(control unit)
 Ignition power supply system
Fuse
C1146 SIDE G-SEN CIRCUIT When a malfunction is detected in side/decel G sig-
nal.
Yaw rate/side/decel G sensor
—Voltage
Connector Terminal
M55 3 Ground Approx. 0 V
Revision: 2010 May2011 QX56

C118E ACCUMULATORBRC-111
< DTC/CIRCUIT DIAGNOSIS > [WITH VDC]
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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