2001 INFINITI QX4 diagram

4 CHECK TCM GROUND CIRCUIT
1. Turn ignition switch to OFF position.
2. Disconnect TCM harness connector.
3. Check continuity between TCM terminals 25, 48 and ground. Refer to wiring diagram Ð AT Ð MAIN.
Continuity should exist.
If OK, check harness for short to ground and short to power.
OK or NG
OK©GO TO 5.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
5 CHECK LAMP CIRCUIT
1. Turn ignition switch to ªONº position.
2. Set overdrive control switch to ªONº position.
3. Check voltage between TCM terminals 13 and ground.
SAT529J
Does battery voltage exist?
Ye s©GO TO 7.
No©GO TO 6.
6 CHECK MALFUNCTIONING ITEM
Check the following items:
IFuse
IO/D OFF indicator lamp
IHarness for short or open between ignition switch and O/D OFF indicator lamp (Main harness)
IRefer to EL-9, ªSchematicº.
IHarness for short or open between O/D OFF indicator lamp and TCM
OK or NG
OK©GO TO 7.
NG©Repair or replace damaged parts.
7 CHECK SYMPTOM
Check again.
OK or NG
OK©INSPECTION END
NG©GO TO 8.
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TROUBLE DIAGNOSES FOR SYMPTOMS
1. O/D OFF Indicator Lamp Does Not Come On (Cont'd)
AT-219

Wiring Diagram Ð SHIFT ÐNBAT0094
MAT921A
A/T SHIFT LOCK SYSTEM
Wiring Diagram Ð SHIFT Ð
AT-266

7 CHECK GROUND CIRCUIT
1. Turn ignition switch to OFF position.
2. Disconnect A/T device harness connector.
3. Check continuity between A/T device harness terminal 6 and ground. Refer to wiring diagram Ð SHIFT Ð.
Continuity should exist.
If OK, check harness for short to ground and short to power.
OK or NG
OK©GO TO 8.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
8 CHECK RELAY CIRCUIT
1. Turn ignition switch to ON and OFF position.
ICheck continuity between terminals 1, 2, 3 and 5.
SAT775J
YesorNo
Ye s©GO TO 9.
No©Replace relay.
9 CHECK PARK POSITION SWITCH
ICheck continuity between A/T device harness terminal 6 and relay (park position switch) harness terminal 1.
SAT180K
OK or NG
OK©GO TO 10.
NG©Replace park position switch.
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A/T SHIFT LOCK SYSTEM
Diagnostic Procedure (Cont'd)
AT-269

BRAKE SYSTEM
SECTION
BR
CONTENTS
PRECAUTIONS...............................................................3
Supplemental Restraint System (SRS)²AIR
BAG²and²SEAT BELT PRE-TENSIONER²...............3
Precautions for Brake System .....................................3
Wiring Diagrams and Trouble Diagnoses....................4
PREPARATION...............................................................5
Special Service Tools ..................................................5
Commercial Service Tools ...........................................5
NOISE, VIBRATION AND HARSHNESS (NVH)
TROUBLESHOOTING.....................................................6
NVH Troubleshooting Chart.........................................6
ON-VEHICLE SERVICE..................................................7
Checking Brake Fluid Level.........................................7
Checking Brake Line ...................................................7
Changing Brake Fluid ..................................................7
Bleeding Brake System ...............................................8
BRAKE HYDRAULIC LINE.............................................9
Hydraulic Circuit...........................................................9
Removal .....................................................................10
Inspection...................................................................10
Installation ..................................................................10
PROPORTIONING VALVE (2WD)................................ 11
Inspection................................................................... 11
Removal and Installation (Built-in type)..................... 11
LOAD SENSING VALVE (4WD)...................................12
Inspection...................................................................12
Removal and Installation ...........................................12
BRAKE PEDAL AND BRACKET..................................14
Removal and Installation ...........................................14
Inspection...................................................................14
Adjustment .................................................................14
MASTER CYLINDER.....................................................16
Removal .....................................................................16
Disassembly...............................................................16
Inspection...................................................................17
Assembly ...................................................................17
Installation ..................................................................18
BRAKE BOOSTER........................................................19
On-vehicle Service.....................................................19OPERATING CHECK...............................................19
AIRTIGHT CHECK...................................................19
Removal .....................................................................19
Inspection...................................................................19
OUTPUT ROD LENGTH CHECK..............................19
Installation ..................................................................20
VACUUM PIPING...........................................................21
Vacuum Hose ............................................................21
Removal and Installation ...........................................21
Inspection...................................................................21
HOSES AND CONNECTORS...................................21
CHECK VALVE........................................................21
FRONT DISC BRAKE...................................................22
Components...............................................................22
Pad Replacement ......................................................22
Removal .....................................................................23
Disassembly...............................................................24
Inspection...................................................................24
CALIPER.................................................................24
ROTOR...................................................................24
Assembly ...................................................................25
Installation ..................................................................25
Brake Burnishing Procedure......................................25
REAR DRUM BRAKE...................................................26
Components...............................................................26
Removal .....................................................................26
Inspection...................................................................27
WHEEL CYLINDER..................................................27
Wheel Cylinder Overhaul...........................................28
Inspection...................................................................28
DRUM.....................................................................28
LINING....................................................................28
Installation ..................................................................28
PARKING BRAKE CONTROL......................................30
Components...............................................................30
Removal and Installation ...........................................30
Inspection...................................................................30
Adjustment .................................................................31
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ABS
DESCRIPTION...............................................................32
Purpose......................................................................32
Operation ...................................................................32
ABS Hydraulic Circuit ................................................32
System Components .................................................33
System Description ....................................................33
SENSOR.................................................................33
CONTROL UNIT (BUILT-IN ABS ACTUATOR AND
ELECTRIC UNIT)
.....................................................33
ABS ACTUATOR AND ELECTRIC UNIT....................33
G SENSOR (4WD MODELS ONLY)..........................34
Component Parts and Harness Connector
Location .....................................................................35
Schematic ..................................................................36
Wiring Diagram - ABS - .............................................37
ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION...............................................................41
Self-diagnosis ............................................................41
FUNCTION..............................................................41
SELF-DIAGNOSIS PROCEDURE..............................41
HOW TO READ SELF-DIAGNOSTIC RESULTS
(MALFUNCTION CODES)
........................................42
HOW TO ERASE SELF-DIAGNOSTIC RESULTS
(MALFUNCTION CODES)
........................................42
CONSULT-II ...............................................................43
CONSULT-II APPLICATION TO ABS..........................43
ECU (ABS CONTROL UNIT) PART NUMBER
MODE
.....................................................................43
CONSULT-II Inspection Procedure............................44
SELF-DIAGNOSIS PROCEDURE..............................44
SELF-DIAGNOSTIC RESULTS MODE.......................45
DATA MONITOR PROCEDURE................................46
ACTIVE TEST PROCEDURE....................................47
DATA MONITOR MODE...........................................48
ACTIVE TEST MODE...............................................48
TROUBLE DIAGNOSIS - INTRODUCTION..................49
How to Perform Trouble Diagnoses for Quick
and Accurate Repair ..................................................49
INTRODUCTION......................................................49
TROUBLE DIAGNOSIS - BASIC INSPECTION...........50
Preliminary Check......................................................50
Ground Circuit Check ................................................53
ABS ACTUATOR AND ELECTRIC UNIT GROUND.....53
TROUBLE DIAGNOSIS - GENERAL
DESCRIPTION...............................................................54
Malfunction Code/Symptom Chart.............................54
TROUBLE DIAGNOSES FOR SELF-DIAGNOSTIC
ITEMS.............................................................................56Wheel Sensor or Rotor ..............................................56
DIAGNOSTIC PROCEDURE.....................................56
ABS Actuator Solenoid Valve or Solenoid Valve
Relay ..........................................................................59
DIAGNOSTIC PROCEDURE.....................................59
Motor Relay or Motor.................................................61
DIAGNOSTIC PROCEDURE.....................................61
Low Voltage ...............................................................63
DIAGNOSTIC PROCEDURE.....................................63
G Sensor and Circuit .................................................65
DIAGNOSTIC PROCEDURE.....................................65
ELECTRICAL COMPONENT INSPECTION................67
Control Unit ................................................................68
DIAGNOSTIC PROCEDURE.....................................68
TROUBLE DIAGNOSES FOR SYMPTOMS.................69
1. ABS Works Frequently ..........................................69
2. Unexpected Pedal Action ......................................69
3. Long Stopping Distance ........................................70
4. ABS Does Not Work ..............................................71
5. Pedal Vibration and Noise.....................................71
6. Warning Lamp Does Not Come On When
Ignition Switch Is Turned On .....................................72
7. Warning Lamp Stays On When Ignition Switch
Is Turned On ..............................................................74
8. Vehicle Vibrates Excessively When ABS Is
Operating ...................................................................77
REMOVAL AND INSTALLATION.................................80
Front Wheel Sensor...................................................80
Rear Wheel Sensor ...................................................80
Front Sensor Rotor ....................................................81
REMOVAL...............................................................81
INSTALLATION........................................................81
Rear Sensor Rotor.....................................................81
REMOVAL...............................................................81
INSTALLATION........................................................81
G Sensor....................................................................81
ABS Actuator and Electric Unit..................................82
REMOVAL...............................................................82
INSTALLATION........................................................82
SERVICE DATA AND SPECIFICATIONS (SDS).........83
General Specifications ...............................................83
Disc Brake .................................................................83
Drum Brake................................................................83
Brake Pedal ...............................................................83
Parking Brake Control ...............................................84
CONTENTS(Cont'd)
BR-2

Wiring Diagrams and Trouble DiagnosesNBBR0003When you read wiring diagrams, refer to the following:
IGI-11, ªHOW TO READ WIRING DIAGRAMSº
IEL-9, ªPOWER SUPPLY ROUTINGº for power distribution circuit
When you perform trouble diagnoses, refer to the following:
IGI-35, ªHOW TO FOLLOW TEST GROUP IN TROUBLE DIAGNOSESº
IGI-24, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENTº
PRECAUTIONS
Wiring Diagrams and Trouble Diagnoses
BR-4

Wiring Diagram Ð ABS ÐNBBR0094
MBR437A
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DESCRIPTIONABS
Wiring Diagram Ð ABS Ð
BR-37

MBR438A
DESCRIPTIONABS
Wiring Diagram Ð ABS Ð (Cont'd)
BR-38