steering INFINITI QX4 2005 Factory Workshop Manual

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
BRC-41
[VDC/TCS/ABS]
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BRC
Revision: October 20052005 QX56
Steering Angle Sensor SystemEFS004XU
INSPECTION PROCEDURE
1. CHECK SELF-DIAGNOSIS RESULT
Check self-diagnosis results.
Is above displayed in self-diagnosis item?
YES >> GO TO 2.
NO >> Inspection End.
2. CHECK CONNECTOR
1. Disconnect steering angle sensor connector M47 and ABS actuator and electric unit (control unit) connec-
tor E125 and check terminals for deformation, disconnection, looseness, or damage. Repair or replace as
necessary.
2. Reconnect connectors and repeat ABS actuator and electric unit (control unit) self-diagnosis.
IS "ST ANGLE SEN CIRCUIT" or "ST ANG SEN COM CIR" DISPLAYED?
YES >> GO TO 3.
NO >> Inspection End.
3. CHECK STEERING ANGLE SENSOR HARNESS
1. Check CAN communication system. Refer to LAN-5, "
CAN COMMUNICATION" .
2. Turn ignition switch OFF and disconnect steering angle sensor
connector M47 and ABS actuator and electric unit (control unit)
connector E125.
3. Check continuity between ABS actuator and electric unit (control
unit) connector E125 and steering angle sensor connector M47.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness.
4. CHECK DATA MONITOR
1. Connect steering angle sensor and ABS actuator and electric unit (control unit) connectors.
2. Use “DATA MONITOR” to check if the status of "STR ANGLE SIG" is normal.
OK or NG
OK >> Perform ABS actuator and electric unit (control unit) self-diagnosis again.
NG >> Replace spiral cable (steering angle sensor) and adjust neutral position of steering angle sensor.
Refer to BRC-62, "
Adjustment of Steering Angle Sensor Neutral Position" .
Self-diagnosis results
ST ANGLE SEN CIRCUIT
ST ANG SEN COM CIR
ABS actuator and
electric unit (con-
trol unit) harness
connector E125Steering angle
sensor
harness con-
nector M47Continuity
11 (L) 3 (L) Yes
15 (P) 4 (P) Yes
WFIA0224E
Steering condition Data monitor
Straight-ahead –3.5 deg to +3.5 deg
Turn wheel to the right by 90°Approx. - 90deg
Turn wheel to the left by 90°Approx. + 90deg

BRC-54
[VDC/TCS/ABS]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: October 20052005 QX56
4. REAR PRESSURE SENSOR INSPECTION
1. Reconnect the rear pressure sensor and ABS actuator and electric unit (control unit) connectors.
2. Use "DATA MONITOR" to check if the status of "PRESS SEN 2" is normal.
OK or NG
OK >> Inspection End.
NG >> Replace rear pressure sensor.
Steering Angle Sensor Safe Mode InspectionEFS00695
INSPECTION PROCEDURE
1. INDICATOR LAMP CHECK
Check that VDC OFF indicator lamp is on.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2. ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Adjust steering angle sensor neutral position. Refer to BRC-62, "
Adjustment of Steering Angle Sensor Neutral
Position" .
OK or NG
OK >> GO TO 3.
NG >> Check steering angle sensor. Refer to BRC-41, "
Steering Angle Sensor System" .
3. INDICATOR LAMP CHECK
Check that VDC OFF indicator lamp is off.
OK or NG
OK >> GO TO 4.
NG >> Perform basic inspection. Refer to BRC-23, "
Basic Inspection" .
4. CHECK SELF-DIAGNOSTIC RESULTS
Perform ABS actuator and electric unit (control unit) self-diagnosis.
NOTE:
When self-diagnostic results show items other than those above, perform repair or replacement for the item
indicated and repeat self-diagnosis.
Is the above displayed on self-diagnosis display?
YES >> Erase error memory.
NO >> Inspection End.ConditionData monitor display (Approx.)
PRESS SEN 2
When brake pedal is depressed Positive value
When brake pedal is released 0 bar
Self-diagnosis results
ST ANGL SEN SAFE

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
BRC-55
[VDC/TCS/ABS]
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BRC
Revision: October 20052005 QX56
CAN Communication System InspectionEFS004Y4
INSPECTION PROCEDURE
1. CHECK CONNECTOR
1. Turn ignition switch OFF, disconnect the ABS actuator and electric unit (control unit) connector, and check
the terminals for deformation, disconnection, looseness, and so on. If there is a malfunction, repair or
replace the terminal.
2. Reconnect connector to perform self-diagnosis.
Is "CAN COMM CIRCUIT" displayed in self-diagnosis display items?
YES >> Print out the self-diagnostic results, and refer to LAN-5, "CAN COMMUNICATION" .
NO >> Connector terminal is loose, damaged, open, or shorted.
Inspection For Self-diagnosis Result "ST ANGLE SEN SIGNAL"EFS004Y5
INSPECTION PROCEDURE
1. DISPLAY SELF-DIAGNOSIS RESULTS
Perform ABS actuator and electric unit (control unit) self-diagnosis.
Do self-diagnosis results indicate anything other than shown above?
YES >> Perform repair or replacement for the item indicated.
NO >> Perform adjustment of steering angle sensor neutral position. GO TO 2.
2. PERFORM SELF-DIAGNOSIS AGAIN
1. Turn the ignition switch to OFF and then to ON and erase self-diagnosis results.
2. Perform ABS actuator and electric unit (control unit) self-diagnosis again.
Are any self-diagnosis results displayed?
YES >> Replace steering angle sensor. Refer to BRC-68, "Removal and Installation" .
NO >> Inspection End.
Inspection For Self-diagnosis Result "DECEL G SEN SET"EFS004Y6
INSPECTION PROCEDURE
1. PERFORM SELF-DIAGNOSIS
Perform ABS actuator and electric unit (control unit) self-diagnosis.
Do self-diagnosis results indicate anything other than shown above?
YES >> Perform repair or replacement for the item indicated.
NO >> Perform calibration of decel G sensor. Refer to BRC-62, "
Calibration of Decel G Sensor" . GO TO
2.
2. PERFORM SELF-DIAGNOSIS AGAIN
1. Turn the ignition switch to OFF and then to ON and erase self-diagnosis results.
2. Perform ABS actuator and electric unit (control unit) self-diagnosis again.
Are any self-diagnosis results displayed?
YES >> Replace yaw rate/side/decel G sensor. Refer to BRC-69, "Removal and Installation" .
NO >> Inspection End.
Self-diagnosis results
ST ANGLE SEN SIGNAL
Self-diagnosis results
DECEL G SEN SET

BRC-62
[VDC/TCS/ABS]
ON-VEHICLE SERVICE
Revision: October 20052005 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

ACTUATOR AND ELECTRIC UNIT (ASSEMBLY)
BRC-67
[VDC/TCS/ABS]
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BRC
Revision: October 20052005 QX56
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
To install, use a flare nut wrench (commercial service tool).

Always tighten brake tubes to specification when installing. Refer to BR-11, "BRAKE PIPING AND
HOSE" .

Never reuse drained brake fluid.

After installation of the ABS actuator and electric unit (control unit), perform the following.
–Refill brake system with new brake fluid. Then bleed the air from the system. Refer to BR-10,
"Bleeding Brake System" .
–Adjust the steering angle sensor. Refer to BRC-62, "Adjustment of Steering Angle Sensor Neutral
Position" .
–Calibrate the decel G sensor. Refer to BRC-62, "Calibration of Decel G Sensor" .

BRC-68
[VDC/TCS/ABS]
STEERING ANGLE SENSOR
Revision: October 20052005 QX56
STEERING ANGLE SENSORPFP:25554
Removal and InstallationEFS004YM
NOTE:
The steering angle sensor is an integral part of the spiral cable.
Refer to SRS-48, "
Removal and Installation" .

DI-42
WARNING CHIME
Revision: October 20052005 QX56
WARNING CHIMEPFP:24814
Component Parts and Harness Connector LocationEKS00BCO
System DescriptionEKS00BCP
FUNCTION
Power is supplied at all times

through 50A fusible link (letter f , located in the fuse and fusible link box)

to BCM terminal 70, and

through 10A fuse [No. 19, located in the fuse block (J/B)]

to key switch and key lock solenoid terminal 3.
With ignition switch in ON or START position, power is supplied

through 10A fuse (No. 59, located in the fuse and relay box)

to BCM terminal 38.
Ground is supplied

to BCM terminal 67

through body grounds M57, M61, and M79.
NOTE:
When ignition key warning chime, light warning chime, and seat belt warning chime are required at the same
time, the priorities for each chime are the following.
1. Light warning chime
2. Ignition key warning chime
1. Combination meter M24 2. Combination switch (lighting switch)
M283. Steering column (view with instru-
ment lower panel LH removed)
4. BCM M18, M19, M20 5. Front door switch LH B8 6. Key switch and key lock solenoid
M27
7. Seat belt buckle pre-tensioner
assembly (seat belt buckle switch)
LH B74
LKIA0692E

EC-6Revision: October 20052005 QX56 DTC P1279, P1289 A/F SENSOR 1 ........................519
Component Description ........................................519
CONSULT-II Reference Value in Data Monitor Mode
.519
On Board Diagnosis Logic ....................................519
DTC Confirmation Procedure ...............................520
Wiring Diagram .....................................................522
Diagnostic Procedure ...........................................525
Removal and Installation ......................................530
DTC P1444 EVAP CANISTER PURGE VOLUME
CONTROL SOLENOID VALVE ...............................531
Description ............................................................531
CONSULT-II Reference Value in Data Monitor Mode
.531
On Board Diagnosis Logic ....................................532
DTC Confirmation Procedure ...............................532
Wiring Diagram .....................................................533
Diagnostic Procedure ...........................................535
Component Inspection ..........................................538
Removal and Installation ......................................538
DTC P1446 EVAP CANISTER VENT CONTROL
VALVE .....................................................................539
Component Description ........................................539
CONSULT-II Reference Value in Data Monitor Mode
.539
On Board Diagnosis Logic ....................................539
DTC Confirmation Procedure ...............................540
Wiring Diagram .....................................................541
Diagnostic Procedure ...........................................542
Component Inspection ..........................................543
DTC P1564 ICC STEERING SWITCH ....................545
Component Description ........................................545
CONSULT-II Reference Value in Data Monitor Mode
.545
On Board Diagnosis Logic ....................................545
DTC Confirmation Procedure ...............................546
Wiring Diagram .....................................................547
Diagnostic Procedure ...........................................548
Component Inspection ..........................................551
DTC P1564 ASCD STEERING SWITCH ................552
Component Description ........................................552
CONSULT-II Reference Value in Data Monitor Mode
.552
On Board Diagnosis Logic ....................................552
DTC Confirmation Procedure ...............................553
Wiring Diagram .....................................................554
Diagnostic Procedure ...........................................555
Component Inspection ..........................................558
DTC P1568 ICC FUNCTION ...................................559
On Board Diagnosis Logic ....................................559
DTC Confirmation Procedure ...............................559
Diagnostic Procedure ...........................................559
DTC P1572 ICC BRAKE SWITCH ..........................560
Component Description ........................................560
CONSULT-II Reference Value in Data Monitor Mode
.560
On Board Diagnosis Logic ....................................560
DTC Confirmation Procedure ...............................561
Wiring Diagram .....................................................562Diagnostic Procedure ............................................ 563
Component Inspection .......................................... 567
DTC P1572 ASCD BRAKE SWITCH ...................... 569
Component Description ........................................ 569
CONSULT-II Reference Value in Data Monitor Mode
. 569
On Board Diagnosis Logic .................................... 569
DTC confirmation Procedure ................................ 570
Wiring Diagram ..................................................... 571
Diagnostic Procedure ............................................ 572
Component Inspection .......................................... 576
DTC P1574 ICC VEHICLE SPEED SENSOR ......... 577
Component Description ........................................ 577
On Board Diagnosis Logic .................................... 577
DTC Confirmation Procedure ................................ 577
Diagnostic Procedure ............................................ 578
DTC P1574 ASCD VEHICLE SPEED SENSOR ..... 579
Component Description ........................................ 579
On Board Diagnosis Logic .................................... 579
DTC Confirmation Procedure ................................ 579
Diagnostic Procedure ............................................ 580
DTC P1706 PNP SWITCH ....................................... 581
Component Description ........................................ 581
CONSULT-II Reference Value in Data Monitor Mode
. 581
On Board Diagnosis Logic .................................... 581
DTC Confirmation Procedure ................................ 581
Overall Function Check ......................................... 582
Wiring Diagram ..................................................... 583
Diagnostic Procedure ............................................ 584
DTC P1805 BRAKE SWITCH ................................. 586
Description ............................................................ 586
CONSULT-II Reference Value in Data Monitor Mode
. 586
On Board Diagnosis Logic .................................... 586
DTC Confirmation Procedure ................................ 586
Wiring Diagram ..................................................... 587
Diagnostic Procedure ............................................ 588
Component Inspection .......................................... 590
DTC P2122, P2123 APP SENSOR ......................... 591
Component Description ........................................ 591
CONSULT-II Reference Value in Data Monitor Mode
. 591
On Board Diagnosis Logic .................................... 591
DTC Confirmation Procedure ................................ 592
Wiring Diagram ..................................................... 593
Diagnostic Procedure ............................................ 594
Component Inspection .......................................... 596
Removal and Installation ....................................... 596
DTC P2127, P2128 APP SENSOR ......................... 597
Component Description ........................................ 597
CONSULT-II Reference Value in Data Monitor Mode
. 597
On Board Diagnosis Logic .................................... 597
DTC Confirmation Procedure ................................ 598
Wiring Diagram ..................................................... 599
Diagnostic Procedure ............................................ 600
Component Inspection .......................................... 603
Removal and Installation ....................................... 603

EC-24Revision: October 2005
ENGINE CONTROL SYSTEM
2005 QX56
Multiport Fuel Injection (MFI) SystemUBS00KZ7
INPUT/OUTPUT SIGNAL CHART
*1: This sensor is not used to control the engine system. This is used only for the on board diagnosis.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). The amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from both the crankshaft position sensor and the mass air
flow sensor.
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.


During warm-up

When starting the engine

During acceleration

Hot-engine operation

When selector lever is changed from N to D

High-load, high-speed operation


During deceleration

During high engine speed operation
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed*
3
Piston position
Fuel injection
& mixture ratio
controlFuel injector Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Knock sensor Engine knocking condition
Battery
Battery voltage*
3
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
ABS actuator and electric unit (control unit)*
2VDC/TCS operation command
Air conditioner switch*
2Air conditioner operation
Wheel sensor*
2Vehicle speed

EC-28Revision: October 2005
AIR CONDITIONING CUT CONTROL
2005 QX56
AIR CONDITIONING CUT CONTROLPFP:23710
Input/Output Signal ChartUBS00KZA
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
System DescriptionUBS00KZB
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned OFF.

When the accelerator pedal is fully depressed.

When cranking the engine.

At high engine speeds.

When the engine coolant temperature becomes excessively high.

When operating power steering during low engine speed or low vehicle speed.

When engine speed is excessively low.

When refrigerant pressure is excessively low or high.
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch*
1Air conditioner ON signal
Air conditioner
cut controlAir conditioner relay Accelerator pedal position sensor Accelerator pedal position
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed*
2
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage*
2
Refrigerant pressure sensor Refrigerant pressure
Power steering pressure sensor Power steering operation
Wheel sensor*
1Vehicle speed