2003 NISSAN X-TRAIL brake sensor

BRC-1
BRAKE CONTROL SYSTEM
F BRAKES
CONTENTS
C
D
E
G
H
I
J
K
L
M
SECTION
A
B
BRC

BRAKE CONTROL SYSTEM
ABS
PRECAUTIONS .......................................................... 4
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 4
Precautions for Brake System .................................. 4
Precautions for Brake Control .................................. 4
PREPARATION ........................................................... 5
Special Service Tools ............................................... 5
SYSTEM DESCRIPTION ............................................ 6
System Diagram ....................................................... 6
ABS Function ........................................................... 6
EBD Function ........................................................... 6
Fail-Safe Function .................................................... 6
ABS, EBD SYSTEM .............................................. 6
Hydraulic Circuit Diagram ........................................ 7
CAN COMMUNICATION ............................................ 8
System Description .................................................. 8
CAN Communication Unit ........................................ 8
TYPE 1 .................................................................. 8
TYPE 2 .................................................................. 9
TROUBLE DIAGNOSIS .............................................11
How to Proceed With Diagnosis .............................. 11
BASIC CONCEPT ................................................ 11
DIAGNOSIS FLOWCHART ................................ 12
ASKING COMPLAINTS ...................................... 13
EXAMPLE OF DIAGNOSIS SHEET ................... 13
Component Parts Location ..................................... 14
Schematic .............................................................. 15
Wiring Diagram — ABS — ..................................... 16
Control Unit Input/Output Signal Standard ............. 24
REFERENCE VALUE FROM CONSULT-II ......... 24
CONSULT- II Functions .......................................... 25
CONSULT-II MAIN FUNCTION ........................... 25
CONSULT-II BASIC OPERATION PROCEDURE
... 25
SELF-DIAGNOSIS .............................................. 27
DATA MONITOR ................................................. 29
ACTIVE TEST ..................................................... 31
Correct and Quick Diagnosis ................................. 33DIAGNOSIS PRECAUTIONS ............................. 33
Basic Inspection ..................................................... 34
BASIC INSPECTION 1 BRAKE FLUID AMOUNT,
LEAKS, AND BRAKE PADS INSPECTION ......... 34
BASIC INSPECTION 2 POWER SYSTEM TER-
MINAL LOOSENESS AND BATTERY INSPEC-
TION .................................................................... 34
BASIC INSPECTION 3 ABS WARNING LAMP ... 34
Inspection 1: Wheel Sensor System ....................... 35
INSPECTION PROCEDURE .............................. 35
Inspection 2: ABS Actuator and Electric Unit (Con-
trol Unit) 1 ............................................................... 37
Inspection 3: ABS Actuator and Electric Unit (Con-
trol Unit) Power Supply and Ground Circuit ............ 37
Inspection 4: ABS Actuator Relay or ABS Motor
Relay Power System .............................................. 38
Inspection 5: ABS Actuator and Electric Unit (Con-
trol Unit) 2 ............................................................... 39
Inspection 6: G Sensor System .............................. 40
Inspection 7: CAN Communication System ............ 42
Symptom 1: ABS Works Frequently ....................... 42
Symptom 2: Unexpected Pedal Reaction ............... 43
Symptom 3: Longer Stopping Distance .................. 43
Symptom 4: ABS Does Not Work ........................... 44
Symptom 5: Pedal Vibration and ABS Operation
Noise ...................................................................... 44
WHEEL SENSORS ................................................... 45
Removal and Installation ........................................ 45
REMOVAL ........................................................... 45
INSTALLATION ................................................... 45
G SENSOR ................................................................ 46
Removal and Installation ........................................ 46
SENSOR ROTOR ..................................................... 47
Removal and Installation ........................................ 47
REMOVAL ........................................................... 47
INSTALLATION ................................................... 47
ABS ACTUATOR AND ELECTRIC UNIT (ASSEM-
BLY) ........................................................................... 48
Removal and Installation ........................................ 48

BRC-2
ESP/TCS/ABS
PRECAUTIONS ......................................................... 49
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ................................................................. 49
Precautions for Brake System ................................ 49
Precautions for Brake Control ................................ 49
PREPARATION ......................................................... 50
Special Service Tools ............................................. 50
ON-VEHICLE SERVICE ............................................ 51
Adjustment of Steering Angle Sensor Neutral Posi-
tion .......................................................................... 51
SYSTEM DESCRIPTION .......................................... 52
System Diagram ..................................................... 52
ESP Function .......................................................... 52
TCS Function .......................................................... 52
ABS Function .......................................................... 53
EBD Function ......................................................... 53
Fail-Safe Function .................................................. 53
ESP/ TCS SYSTEM ............................................ 53
ABS, EBD SYSTEM ............................................ 53
Hydraulic Circuit Diagram ....................................... 54
CAN COMMUNICATION ........................................... 55
System Description ................................................. 55
CAN Communication Unit ....................................... 55
TYPE 3/TYPE4 .................................................... 55
TYPE 5 ................................................................ 56
TROUBLE DIAGNOSIS ............................................ 58
How to Proceed With Diagnosis ............................. 58
BASIC CONCEPT ............................................... 58
DIAGNOSIS FLOWCHART ................................. 59
ASKING COMPLAINTS ....................................... 60
EXAMPLE OF DIAGNOSIS SHEET .................... 60
Component Parts and Harness Connector Location ... 61
Schematic ............................................................... 62
Wiring Diagram —ESP/TCS/ABS— ..................... 63
LHD MODEL ........................................................ 63
RHD MODEL ....................................................... 69
Control Unit Input/Output Signal Standard .............. 75
REFERENCE VALUE FROM CONSULT-II ......... 75
CONSULT-II Functions ........................................... 77
CONSULT-II MAIN FUNCTION ........................... 77
CONSULT-II BASIC OPERATION PROCEDURE
... 77
SELF-DIAGNOSIS .............................................. 79
DATA MONITOR .................................................. 81
ACTIVE TEST ..................................................... 84
For Fast and Accurate Diagnosis ........................... 86
PRECAUTIONS FOR DIAGNOSIS ..................... 86
Basic Inspection ..................................................... 87
BASIC INSPECTION 1 BRAKE FLUID AMOUNT,
LEAKS, AND BRAKE PADS INSPECTION ......... 87
BASIC INSPECTION 2 POWER SYSTEM TER-
MINAL LOOSENESS AND BATTERY INSPEC-
TION .................................................................... 87
BASIC INSPECTION 3 ABS WARNING LAMP,
ESP OFF INDICATOR LAMP, SLIP INDICATOR
LAMP AND BRAKE WARNING LAMP INSPEC-TION .................................................................... 88
Inspection 1 Wheel Sensor System ........................ 89
INSPECTION PROCEDURE ............................... 89
Inspection 2 Engine System ................................... 91
Inspection 3 ESP/TCS/ABS Control Unit System ... 91
Inspection 4 Pressure Sensor and the Circuit
between Pressure Sensor and ESP/TCS/ABS Con-
trol Unit. ................................................................... 91
Inspection 5 Steering Angle Sensor and Circuit
between Steering Angle Sensor and ESP/TCS/ABS
Control Unit. ............................................................ 93
Inspection 6 Yaw Rate/Side G sensor and the Circuit
between Yaw Rate/Side G sensor and ESP/TCS/
ABS Control Unit. .................................................... 95
Inspection 7 Solenoid Valve, ESP Switch-over Sole-
noid Valve and Circuit ............................................. 96
Inspection 8 Actuator Motor, Motor Relay and Circuit
... 99
Inspection 9 Actuator Relay and Circuit ................101
Inspection 10 Stop Lamp Switch and Circuit .........103
Inspection 11 ESP/TCS/ABS Control Unit Power
Supply Circuit ........................................................103
Inspection 12 When “EMERGENCY BRAKE” is
indicated in the Self-Diagnosis Results .................105
Inspection 13 When “ST ANG SEN SIGNAL” is Indi-
cated in the Self-Diagnosis Results ......................105
Inspection 14 Brake Fluid Level of Reservoir Tank,
Communication Circuit between ESP/TCS/ABS
Control Unit and Brake Fluid Level Warning Switch .106
Inspection 15 CAN Communication Circuit, ESP/
TCS/ABS Control Unit and Steering Angle Sensor .107
Component Check ................................................107
ESP OFF SWITCH ............................................107
ESP RELAY BOX ...............................................107
ESP ACTUATOR ...............................................108
Symptom 1: ABS Works Frequently. .....................110
Symptom 2: Unexpected Pedal Action .................110
Symptom 3: Longer Stopping Distance ................. 111
Symptom 4: ABS Does Not Work. ........................112
Symptom 5: Pedal Vibration and Noise ................112
Symptom 6: ESP OFF Indicator Lamp Does Not Illu-
minate ...................................................................113
Symptom 7: SLIP Indicator Lamp Does Not Illumi-
nate .......................................................................114
Symptom 8: Vehicle Jerks During ESP/TCS/ABS
Control ..................................................................114
WHEEL SENSORS .................................................116
Removal and Installation .......................................116
SENSOR ROTOR ....................................................117
Removal and Installation .......................................117
REMOVAL ..........................................................117
INSTALLATION ..................................................117
ESP/TCS/ABS CONTROL UNIT .............................118
Removal and Installation .......................................118
REMOVAL ..........................................................118
INSTALLATION ..................................................118
ESP/TCS/ABS ACTUATOR AND RELAY BOX ......119
Removal and Installation .......................................119

BRC-8
[ABS]
CAN COMMUNICATION

CAN COMMUNICATIONPFP:23710
System DescriptionEFS0055R
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
CAN Communication UnitEFS0055W
×: Applicable
TYPE 1
System diagram
Body typeWagon
Axle4WD
Engine QR20DE/QR25DE QR25DE YD22DDTi QR25DE
Transmission M/T A/T M/T A/T
Brake control ABS ESP
CAN communication unit
ECM×××××
TCM××
ABS actuator and electric unit (control unit)××
ESP/TCS/ABS control unit×××
Steering angle sensor×××
4WD control unit×××××
Combination meter×××××
CAN communication typeBRC-8, "
TYPE
1"
BRC-9, "TYPE
2"BRC-55, "TYPE 3/TYPE4"BRC-56,
"TYPE 5"
PKIA6458E

BRC-24
[ABS]
TROUBLE DIAGNOSIS

Control Unit Input/Output Signal StandardEFS004GA
REFERENCE VALUE FROM CONSULT-II
CAUTION:
The display shows the control unit calculation data, so a normal value might be displayed even in the
event the output circuit (harness) is open or short - circulated.
Note 1: Confirm tyre pressure is normal.
Note 2: ABS warning lamp ON/OFF timing
ON: For approximately 1 second after the ignition switch is turned on or when an error is detected.
OFF: Approximately 1 second after the ignition switch is turned on (when system is normal).Monitor item Display ContentData monitor
Reference: Error inspec-
tion checklist
ConditionReference values
for normal opera-
tion
FR LH SENSOR
FR RH SENSOR
RR LH SENSOR
RR RH SENSORWheel speed calcu-
lated using signals
from all four wheel
sensorsVehicle stopped 0 km/h (0 MPH)
BRC-35, "
Inspection 1:
Wheel Sensor System"While driving (Note 1)Nearly matches
the speedometer
display (± 10% or
less)
DOCILE G-SEN. 1
DOCILE G-SEN. 2Fore-and-aft G
detected by G sensorWhen vehicle is stopped on
level groundOFF
BRC-40, "
Inspection 6: G
Sensor System"When G sensor is tilted toward
the front with G sensor mount-
ing bolt removedON
ABS IN SOL
ABS OUT SOLOperation status of all
solenoidsWhen the actuator solenoid
operates or during a fail-safeON
BRC-38, "
Inspection 4:
ABS Actuator Relay or
ABS Motor Relay Power
System"
When the actuator relay oper-
ates and the actuator solenoid
does not operateOFF
STOP LAMP SW Brake pedal operationBrake pedal depressed ON
Stop lamp switch circuit
Brake pedal not depressed OFF
MOTOR RELAYMotor and motor relay
operation statusWhen the motor relay and
motor are operatingON
BRC-38, "
Inspection 4:
ABS Actuator Relay or
ABS Motor Relay Power
System"
When the motor relay and
motor are not operatingOFF
ACTUATOR RELAYActuator relay opera-
tion statusWhen the actuator relay is
operatingOFF
When the actuator relay is not
operatingON
ABS WARN LAMPABS warning lamp on
condition (Note 2)ABS warning lamp ON ONBRC-34, "
BASIC
INSPECTION 3 ABS
WARNING LAMP"ABS warning lamp OFF OFF
BATTERY VOLTBattery voltage sup-
plied to ABS actuator
and electric unit (con-
trol unit) Ignition switch ON 10 - 16VBRC-37, "
Inspection 3:
ABS Actuator and Elec-
tric Unit (Control Unit)
Power Supply and
Ground Circuit"
EBD FAIL SIG
ABS FAIL SIGFail signal statusEBD Fail
ABS FailON
EBD system
ABS system EBD normal
ABS normalOFF
EBD SIGNAL
ABS SIGNALEBD operation
ABS operationEBD active
ABS activeON
EBD not active
ABS not activeOFF

BRC-28
[ABS]
TROUBLE DIAGNOSIS

Display Item List
Suspect Systems Malfunction detecting condition Inspection system
RR RH SENSOR-1 When the circuit in the rear RH wheel sensor is open.
BRC-35, "
Inspection 1:
Wheel Sensor Sys-
tem"(Note 1) RR LH SENSOR-1 When the circuit in the rear LH wheel sensor is open.
FR RH SENSOR-1 When the circuit in the front RH wheel sensor is open.
FR LH SENSOR-1 When the circuit in the front LH wheel sensor is open.
FR LH SENSOR-2When the circuit in the front LH wheel sensor is short-circuited.
Or when the sensor power voltage is outside the standard. When
the distance between the wheel sensor and sensor rotor is too
large and the sensor pulse cannot be recognized by the control
unit.
RR RH SENSOR-2When the circuit in the rear RH wheel sensor is short-circuited.
Or when the sensor power voltage is outside the standard. When
the distance between the wheel sensor and sensor rotor is too
large and the sensor pulse cannot be recognized by the control
unit.
FR RH SENSOR-2When the circuit in the front RH wheel sensor is short-circuited.
Or when the sensor power voltage is outside the standard. When
the distance between the wheel sensor and sensor rotor is too
large and the sensor pulse cannot be recognized by the control
unit.
RR LH SENSOR-2When the circuit in the rear LH wheel sensor is short-circuited. Or
when the sensor power voltage is outside the standard. When
the distance between the wheel sensor and sensor rotor is too
large and the sensor pulse cannot be recognized by the control
unit.
MAIN RELAYWhen the control unit detects an error in the actuator relay sys-
tem.BRC-38, "
Inspection 4:
ABS Actuator Relay or
ABS Motor Relay Power
System"
FR LH IN ABS SOLWhen the control unit detects an error in the front left inlet sole-
noid system.
BRC-38, "
Inspection 4:
ABS Actuator Relay or
ABS Motor Relay Power
System"
FR LH OUT ABS SOLWhen the control unit detects an error in the front left outlet sole-
noid system.
RR RH IN ABS SOLWhen the control unit detects an error in the rear right inlet sole-
noid system.
RR RH OUT ABS SOLWhen the control unit detects an error in the rear right outlet sole-
noid system.
FR RH IN ABS SOLWhen the control unit detects an error in the front right inlet sole-
noid system.
FR RH OUT ABS SOLWhen the control unit detects an error in the front right outlet
solenoid system.
RR LH IN ABS SOLWhen the control unit detects an error in the rear left inlet sole-
noid system.
RR LH OUT ABS SOLWhen the control unit detects an error in the rear left outlet sole-
noid system.
LOW POWER VOLTAGEWhen the ABS actuator and electric unit power voltage is lower
than normal. BRC-37, "
Inspection 3:
ABS Actuator and Elec-
tric Unit (Control Unit)
Power Supply and
Ground Circuit"
EMERGENCY BRAKEWhen the ABS actuator and electric unit malfunctions (pressure
increase is too much or too little).BRC-39, "
Inspection 5:
ABS Actuator and Elec-
tric Unit (Control Unit) 2"
ABS CONTROLLERWhen there is an internal error in the ABS actuator and electric
unit.BRC-37, "
Inspection 2:
ABS Actuator and Elec-
tric Unit (Control Unit) 1"

BRC-42
[ABS]
TROUBLE DIAGNOSIS

OK or NG
OK >> ABS actuator and electric unit (control unit) malfunction. Replace ABS actuator and electric unit
(control unit).
NG >> G sensor malfunction. Replace G sensor.
Inspection 7: CAN Communication SystemEFS004HI
INSPECTION PROCEDURE
1. CHECK CONNECTOR
1. Turn ignition switch OFF, disconnect the ABS actuator and electric unit (control unit) connector, and check
the terminal 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 the self-diagnosis display items?
YES >> Print out the self-diagnostic results, and refer to LAN-4, "CAN Communication Unit" .
NO >> Connector terminal connector is loose, damaged, open, or shorted.
Symptom 1: ABS Works FrequentlyEFS004HJ
1. CHECK START
Check longitudinal brake force distribution using a brake tester.
OK or NG
OK >> GO TO 2.
NG >> Check brake system.
2. CHECK FRONT AND REAR AXLE
Check to make sure that there is no excessive play in the front and rear axles. Refer to Front: FAX-7, "
On-
Vehicle Inspection" , Rear: RAX-6, "On-Vehicle Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Repair.
3. CHECK WHEEL SENSOR AND SENSOR ROTOR
Check wheel sensor and sensor rotor for the following.

Sensor installation for damage

Sensor rotor installation for damage

Sensor connector engagement

Sensor harness
OK or NG
OK >> GO TO 4.
NG >>

Replace wheel sensor or sensor rotor.

Repair harness.
4. CHECK ABS WARNING LAMP DISPLAY
Make sure that the warning lamp turns off approximately 1 second after the key switch is turned on or when
driving.
OK or NG
OK >> Normal
NG >> Perform self-diagnosis. Refer to BRC-27, "
SELF-DIAGNOSIS" .

TROUBLE DIAGNOSIS
BRC-43
[ABS]
C
D
E
G
H
I
J
K
L
MA
B
BRC

Symptom 2: Unexpected Pedal ReactionEFS004HK
1. CHECK BRAKE PEDAL STROKE
Check brake pedal stroke. Refer to BR-6, "
On-Vehicle Inspection and Adjustment" .
Is the stroke too large?
YES >>
Bleed air from the brake piping. Refer to BR-9, "Bleeding Brake System" .

Check brake pedal, brake booster, and master cylinder for mount play, looseness, brake sys-
tem fluid leakage, etc. Repair if necessary. Refer to Brake pedal: BR-7, "
Components" , brake
booster and master cylinder: BR-23, "
Removal and Installation" .
NO >> GO TO 2.
2. PERFORMANCE CHECK
Disconnect ABS actuator and electric unit (control unit) connector to deactivate ABS. Check if braking force is
normal in this condition. Connect connector after inspection.
OK or NG
OK >> GO TO 3. Wheel Sensor Inspection in BRC-42, "Symptom 1: ABS Works Frequently" .
NG >> Check brake system.
Symptom 3: Longer Stopping DistanceEFS004HL
CAUTION:
The stopping distance on slippery road surfaces might be longer with the ABS operating than when
the ABS is not operating.
1. PERFORMANCE CHECK
Turn ignition switch OFF. Disconnect ABS actuator and electric unit (control unit) connector to deactivate ABS.
In this condition, check stopping distance. After inspection, connect connector.
OK or NG
OK >> GO TO BRC-42, "Symptom 1: ABS Works Frequently" .
NG >>

Bleed air from the brake piping. Refer to BR-9, "Bleeding Brake System" .

Check brake system.

BRC-44
[ABS]
TROUBLE DIAGNOSIS

Symptom 4: ABS Does Not WorkEFS004HM
CAUTION:
ABS does not operate when speed is 10 km/h or lower.
1. CHECK ABS WARNING LAMP DISPLAY
Make sure that the warning lamp turns off approximately 1 second after the key switch is turned on or when
driving.
OK or NG
OK >> GO TO 3. Check wheel sensor and sensor rotor in BRC-42, "Symptom 1: ABS Works Frequently"
.
NG >> Perform self-diagnosis. Refer to BRC-27, "
SELF-DIAGNOSIS" .
Symptom 5: Pedal Vibration and ABS Operation NoiseEFS004HN
CAUTION:
Under the following conditions, ABS is activated and vibration is felt when brake pedal is lightly
depressed (just place a foot on it). However, this is normal.

When shifting gears

When driving on slippery road

During cornering at high speed

When passing over bumps or grooves (Approx. 50 mm or more)

When pulling away just after starting engine (Approx. 10 km/h or more)
1. SYMPTOM CHECK 1
Check if pedal vibration or operation sounds occur when the engine is started.
OK or NG
OK >> GO TO 2.
NG >> Perform self-diagnosis. Refer to BRC-27, "
SELF-DIAGNOSIS" .
2. SYMPTOM CHECK 2
Check symptoms when electrical component (headlamps, etc.) Switches are operated.
Do symptoms occur?
YES >> Check if there is a radio, antenna, antenna lead wire, or wiring close to the control unit. If there is,
move it farther away.
NG >> GO TO 3. Check wheel sensor and sensor rotor in BRC-42, "
Symptom 1: ABS Works Frequently"
.