2011 INFINITI QX56 power steering

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
BCM
BCS-55
< ECU DIAGNOSIS INFORMATION >
C
D E
F
G H
I
J
K L
B A
O P
N
B2603: SHIFT POSI STATUS Inhibit steering lock
500 ms after any of the following BCM recognition conditions are fulfilled
Status 1
- Ignition switch is in the ON position
- Selector lever P position switch signal: Except P position (12 V)
- Selector lever P/N position signal: Except P and N positions (0 V)
Status 2
- Ignition switch is in the ON position
- Selector lever P position switch signal: P position (0 V)
- Selector lever P/N position signal: P or N positions (12 V)
B2604: PNP/CLUTCH SW Inhibit steering lock 500 ms after any of the following BCM recognition conditions are fulfilled
Status 1
- Ignition switch is in the ON position
- Selector lever P/N position signal: P or N position (12 V)
- Shift position signal (CAN): P or N position
Status 2
- Ignition switch is in the ON position
- Selector lever P/N position signal: Except P and N positions (0 V)
- Shift position signal (CAN): Except P and N position
B2605: PNP/CLUTCH SW Inhibit steering lock 500 ms after any of the following BCM recognition conditions are fulfilled
Status 1
- Power position: IGN
- Selector lever P/N position signal: Except P and N positions (0 V)
- Interlock/PNP switch signal (CAN): OFF
Status 2
- Ignition switch is in the ON position
- Selector lever P/N position signal: P or N position (12 V)
- Interlock/PNP switch signal (CAN): ON
B2608: STARTER RELAY Inhibit engine cranking 500 ms after the following signal communication status becomes con-
sistent
 Starter motor re
lay control signal
 Starter relay status signal (CAN)
B2609: S/L STATUS  Inhibit engine crank-
ing
 Inhibit steering lock When the following steering lock conditions agree
 BCM steering lock control status
 Steering lock condition No. 1 signal status
 Steering lock condition No. 2 signal status
B260B: STEERING LOCK UNIT Inhibit steering lock Erase DTC
B260D: STEERING LOCK UNIT Inhibit steering lock Erase DTC
B260F: ENG STATE SIG LOST Inhibit engine cranking When any of the following conditions are fulfilled
 Power position changes to ACC
 Receives engine status signal (CAN)
B2612: S/L STATUS  Inhibit engine crank-
ing
 Inhibit steering lock When any of the following conditions are fulfilled
 Steering lock unit status signal (CAN) is received normally
 The BCM steering lock control status matches the steering lock status
recognized by the steering lock unit status signal (CAN from IPDM E/
R)
B2619: BCM Inhibit engine cranking 1 second after the steering lock unit power supply output control inside
BCM becomes normal
B26EF: STRG LCK RELAY OFF Inhibit engine cranking When the following conditions are fulfilled
 Steering lock relay signal (CAN): ON
 Steering lock unit status signal (CAN): ON
B26F0: STRG LCK RELAY ON Inhibit engine cranking When the following conditions are fulfilled
 Steering lock relay signal (CAN): OFF
 Steering lock unit status signal (CAN): OFF
B26F1: IGN RELAY OFF Inhibit engine cranking When the following conditions are fulfilled
 Ignition switch ON signal (CAN: Transmitted from BCM): ON
 Ignition switch ON signal (CAN: Transmitted from IPDM E/R): ON
B26F2: IGN RELAY ON Inhibit engine cranking When the following conditions are fulfilled
 Ignition switch ON signal (CAN: Transmitted from BCM): OFF
 Ignition switch ON signal (CAN: Transmitted from IPDM E/R): OFF
Display contents of CONSULT Fail-safe Cancellation
Revision: 2010 May2011 QX56

BCS-56
< ECU DIAGNOSIS INFORMATION >
BCM
FAIL-SAFE CONTROL BY RAIN SENSOR MALFUNCTION
BCM detects the light and rain sensor serial link error and the rain sensor malfunction.
BCM controls the following fail-safe when rain sensor has a malfunction.
 Front wiper switch AUTO and sensing rain drop: The condition just before the activation of fail-safe is main-
tained until the front wiper switch is turned OFF.
 Front wiper switch AUTO and not sensing rain drop: Front wiper is LO operation until the front wiper switch is
turned off.
REAR WIPER MOTOR PROTECTION
BCM detects the rear wiper stopping position acco rding to the rear wiper stop position signal.
When the rear wiper stop position signal does not c hange for more than 5 seconds while driving the rear
wiper, BCM stops power supply to protect the rear wiper motor.
Condition of cancellation
1. More than 1 minute is passed after the rear wiper stop.
2. Turn rear wiper switch OFF.
3. Operate the rear wiper swit ch or rear washer switch.
FAIL-SAFE CONTROL OF COMBINATION SWITCH READING FUNCTION CAUSED BY LOW
POWER SUPPLY VOLTAGE
If voltage of battery power supply lower, BCM maintain s combination switch reading to the status when input
voltage is less than approximately 9 V.
NOTE:
When voltage of battery power supply is approximately 9 V or more, combination switch reading function
returns to normal operation.
DTC Inspection Priority ChartINFOID:0000000006274821
If some DTCs are displayed at the same time, perfo rm inspections one by one based on the following priority
chart.
B26F3: START CONT RLY ON Inhibit engine cranking When the following conditions are fulfilled
 Starter control relay signal (CAN: Transmitted from BCM): OFF
 Starter control relay signal (CAN: Transmitted from IPDM E/R): OFF
B26F4: START CONT RLY OFF Inhibit engine cranking When the following conditions are fulfilled
 Starter control relay signal (CAN: Transmitted from BCM): ON
 Starter control relay signal (CAN: Transmitted from IPDM E/R): ON
B26F7: BCM Inhibit engine cranking
by Intelligent Key sys-
temWhen room antenna and luggage room antenna functions normally
U0415: VEHICLE SPEED Inhibit steering lock When vehicle speed signal (Meter) (CAN) is received normally
Display contents of CONSULT Fail-safe Cancellation
Priority DTC
1 B2562: LOW VOLTAGE
2  U1000: CAN COMM
 U1010: CONTROL UNIT (CAN)
3  B2192: ID DISCORD BCM-ECM
 B2193: CHAIN OF BCM-ECM
 B2195: ANTI-SCANNING
 B2198: NATS ANTENNA AMP
Revision: 2010 May2011 QX56

PRECAUTIONSBR-3
< PRECAUTION >
C
DE
G H
I
J
K L
M A
B
BR
N
O P
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006228171
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the “SRS AIR BAG” and “SEAT BELT” of this
Service Manual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision that would result in air ba g inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
 Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the “SRS AIR BAG”.
 Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
 When working near the Air Bag Diagnosis Sensor Unit or other Air Bag System sensors with the
ignition ON or engine running, DO NOT use air or electric power tools or strike near the sensor(s)
with a hammer. Heavy vibration could activate the sensor(s) and deploy the air bag(s), possibly
causing serious injury.
 When using air or electric power tools or hammers , always switch the ignition OFF, disconnect the
battery, and wait at least 3 minutes before performing any service.
Precaution Necessary for Steering Wh eel Rotation after Battery Disconnect
INFOID:0000000006228172
NOTE:
 Before removing and installing any control units, first tu rn the push-button ignition switch to the LOCK posi-
tion, then disconnect both battery cables.
 After finishing work, confirm that all control unit connectors are connected properly, then re-connect both
battery cables.
 Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If a DTC is detected, perform trouble diagnos is according to self-diagnosis results.
For vehicle with steering lock unit, if the battery is disconnected or discharged, the steering wheel will lock and
cannot be turned.
If turning the steering wheel is required with the batte ry disconnected or discharged, follow the operation pro-
cedure below before starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Turn the push-button ignition switch to ACC position. (At this time, the steering lock will be released.)
3. Disconnect both battery cables. The steering lock wil l remain released with both battery cables discon-
nected and the steering wheel can be turned.
4. Perform the necessary repair operation.
Revision: 2010 May2011 QX56

BR-24
< REMOVAL AND INSTALLATION >
BRAKE PIPING
Never reuse the copper washer.
3. Install the brake hose L-pin by aligning it with the brake caliper assembly positioning hole, and tighten the union bolt (1) to the
specified torque.
4. Install the brake tube to the brake hose, temporarily tighten the flare nut by hand until it does not rotate further, and fix the brake
hose to the bracket with the lock plate.
CAUTION:
Check that all brake hose or brake tube are not twisted and
bent.
5. Tighten the flare nut to the specified torque with a crowfoot and torque wrench.
CAUTION:
Never scratch the flare nut and the brake tube.
6. Tighten the brake hose mounting nuts to the specified torque. CAUTION:
Never reuse the brake hose mounting nuts.
7. Perform the air bleeding. Refer to BR-11, "
Bleeding Brake System".
8. Install tires with power tool. Refer to WT-64, "
Exploded View".
9. Perform inspection after installation. Refer to BR-24, "
FRONT : Inspection".
FRONT : InspectionINFOID:0000000006222478
INSPECTION AFTER INSTALLATION
1. Check the brake hoses and tubes for the following: no scratches; no twist and deformation; no interfer-
ence with other components when steering the steering wheel; no looseness at connections.
2. Depress the brake pedal with a force of 785 N (80 kg, 176 lb) and hold down the pedal for approx. 5 sec- onds with the engine running. Check for any fluid leakage.
CAUTION:
Retighten the applicable connection to the specified torque and repair any abnormal (damaged,
worn or deformed) part if any brake fluid leakage is present.
REAR
JPFIA0012ZZ
Revision: 2010 May2011 QX56

BR-26
< REMOVAL AND INSTALLATION >
BRAKE PIPING
REAR : Removal and Installation
INFOID:0000000006222481
REMOVAL
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 depress the brake pedal. Brake fluid may spl ash while removing the brake hose or brake tube.
1. Remove tires with power tool.
2. Drain brake fluid. Refer to BR-10, "
Draining".
3. Loosen the flare nut with a flare nut wrench and separate the brake tube and the brake hose. CAUTION:
 Never scratch the flare nut and the brake tube.
 Never bend sharply, twist or strongly pull out the brake hose or brake tube.
 Cover open end of brake hose or brake tube wh en disconnecting to prevent entrance of dirt.
4. Remove the union bolt and copper washers, and remove the brake hose from the brake caliper assembly.
5. Remove the lock plate and remove the brake hose.
INSTALLATION
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 depress the brake pedal. Brake fluid may spl ash while removing the brake hose or brake tube.
1. Assemble the union bolt and the copper washers to the brake hose. CAUTION:
Never reuse the copper washer.
2. Align the brake hose pin to the projection (A) of the brake caliper
assembly and tighten the union bolt (1) to the specified torque.
3. Install the brake tube to the brake hose, temporarily tighten the flare nut by hand until it does not rotate further, and fix the brake
hose to the bracket with the lock plate.
CAUTION:
Check that all brake hose or brake tube are not twisted and
bent.
4. Tighten the flare nut to the specified torque with a crowfoot and torque wrench.
CAUTION:
Never scratch the flare nut and the brake tube.
5. Perform the air bleeding. Refer to BR-11, "
Bleeding Brake System".
6. Install tires with power tool. Refer to WT-64, "
Exploded View".
7. Perform inspection after installation. Refer to BR-26, "
REAR : Inspection".
REAR : InspectionINFOID:0000000006222482
INSPECTION AFTER INSTALLATION
1. Check the brake hoses and tubes for the following: no scratches; no twist and deformation; no interfer-
ence with other components when steering the steering wheel; no looseness at connections.
1. Front disc brake 2. Connector 3. Hydraulic booster assembly
4. Rear disc brake
A. Brake hose B. Brake tube
: Flare nut
: Union bolt
JPFIA0099ZZ
Revision: 2010 May2011 QX56

BRC-2
ADDITIONAL SERVICE WHEN REPLACING
ABS ACTUATOR AND ELECTRIC UNIT
(CONTROL UNIT) ..............................................
63
Description ........................................................... ...63
ADJUSTMENT OF STEERING ANGLE SEN-
SOR NEUTRAL POSITION ...............................
64
Description ........................................................... ...64
Work Procedure ......................................................64
CALIBRATION OF DECEL G SENSOR ...........66
Description ........................................................... ...66
Work Procedure ......................................................66
DTC/CIRCUIT DIAGNOSIS ...................... ...68
C1101, C1102, C1103, C1104 WHEEL SEN-
SOR ................................................................. ...
68
DTC Logic ............................................................ ...68
Diagnosis Procedure ..............................................68
C1105, C1106, C1107, C1108 WHEEL SEN-
SOR ....................................................................
70
DTC Logic ............................................................ ...70
Diagnosis Procedure ..............................................70
C1109 POWER AND GROUND SYSTEM .........72
Description ........................................................... ...72
DTC Logic ...............................................................72
Diagnosis Procedure ..............................................72
C1111 PUMP MOTOR .......................................75
DTC Logic ............................................................ ...75
Diagnosis Procedure ..............................................75
C1115 WHEEL SENSOR ...................................77
DTC Logic ............................................................ ...77
Diagnosis Procedure ..............................................77
C1116 STOP LAMP SWITCH ............................79
DTC Logic ............................................................ ...79
Diagnosis Procedure ..............................................79
Component Inspection (Stop lamp Switch) ............85
Component Inspection (Stop Lamp Relay) .............86
C1118 TRANSFER CONTROL UNIT ................87
DTC Logic ............................................................ ...87
Diagnosis Procedure ..............................................87
C1120, C1122, C1124, C1126 ABS IN VALVE
SYSTEM .......................................................... ...
88
DTC Logic ............................................................ ...88
Diagnosis Procedure ..............................................88
C1121, C1123, C1125, C1127 ABS OUT
VALVE SYSTEM ................................................
90
DTC Logic ............................................................ ...90
Diagnosis Procedure ..............................................90
C1130 ENGINE SIGNAL ...................................92
DTC Logic ............................................................ ...92
Diagnosis Procedure ............................................ ...92
C1140 ACTUATOR RELAY SYSTEM ..............93
DTC Logic ............................................................ ...93
Diagnosis Procedure ...............................................93
C1142 PRESS SENSOR ...................................95
DTC Logic ............................................................ ...95
Diagnosis Procedure ...............................................95
C1143 STEERING ANGLE SENSOR ...............97
DTC Logic ............................................................ ...97
Diagnosis Procedure ...............................................97
C1144 INCOMPLETE STEERING ANGLE
SENSOR ADJUSTMENT ..................................
99
DTC Logic ............................................................ ...99
Diagnosis Procedure ...............................................99
C1145, C1146 YAW RATE/SIDE/DECEL G
SENSOR ...........................................................
100
DTC Logic ............................................................ .100
Diagnosis Procedure .............................................100
C1155 BRAKE FLUID LEVEL SWITCH ..........103
DTC Logic ............................................................ .103
Diagnosis Procedure .............................................103
Component Inspection ..........................................104
C1160 DECEL G SEN SET ..............................105
DTC Logic ............................................................ .105
Diagnosis Procedure .............................................105
C1164, C1165 CV SYSTEM .............................106
DTC Logic ............................................................ .106
Diagnosis Procedure .............................................106
C1166, C1167 SV SYSTEM .............................108
DTC Logic ............................................................ .108
Diagnosis Procedure .............................................108
C1170 VARIANT CODING ...............................110
DTC Logic ............................................................ .110
Diagnosis Procedure .............................................110
C118E ACCUMULATOR ..................................111
DTC Logic ............................................................ .111
Diagnosis Procedure .............................................111
U1000 CAN COMM CIRCUIT ...........................112
Description ........................................................... .112
DTC Logic .............................................................112
Diagnosis Procedure .............................................112
POWER SUPPLY AND GROUND CIRCUIT ....113
Description ........................................................... .113
Diagnosis Procedure .............................................113
PARKING BRAKE SWITCH .............................117
Component Function Check ................................ .117
Diagnosis Procedure .............................................117
Component Inspection ..........................................118
Revision: 2010 May2011 QX56

PRECAUTIONSBRC-5
< PRECAUTION > [WITH VDC]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006228174
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the “SRS AIR BAG” and “SEAT BELT” of this
Service Manual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision that would result in air ba g inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
 Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the “SRS AIR BAG”.
 Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
 When working near the Air Bag Diagnosis Sensor Unit or other Air Bag System sensors with the
ignition ON or engine running, DO NOT use air or electric power tools or strike near the sensor(s)
with a hammer. Heavy vibration could activate the sensor(s) and deploy the air bag(s), possibly
causing serious injury.
 When using air or electric power tools or hammers , always switch the ignition OFF, disconnect the
battery, and wait at least 3 minutes before performing any service.
Precaution Necessary for Steering Wh eel Rotation after Battery Disconnect
INFOID:0000000006228175
NOTE:
 Before removing and installing any control units, first tu rn the push-button ignition switch to the LOCK posi-
tion, then disconnect both battery cables.
 After finishing work, confirm that all control unit connectors are connected properly, then re-connect both
battery cables.
 Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If a DTC is detected, perform trouble diagnos is according to self-diagnosis results.
For vehicle with steering lock unit, if the battery is disconnected or discharged, the steering wheel will lock and
cannot be turned.
If turning the steering wheel is required with the batte ry disconnected or discharged, follow the operation pro-
cedure below before starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Turn the push-button ignition switch to ACC position. (At this time, the steering lock will be released.)
3. Disconnect both battery cables. The steering lock wil l remain released with both battery cables discon-
nected and the steering wheel can be turned.
4. Perform the necessary repair operation.
Revision: 2010 May2011 QX56