2007 INFINITI M35 control unit

SB-1
SEAT BELTS
H RESTRAINTS
CONTENTS
C
D
E
F
G
I
J
K
L
M
SECTION SB
A
B
SB
Revision: 2007 April2007 M35/M45
SEAT BELTS
PRECAUTIONS .......................................................... 2
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 2
Precaution for Seat Belt Service .............................. 2
AFTER A COLLISION ........................................... 2
PRE-CRASH SEAT BELT .......................................... 3
Component Parts and Harness Connector Location ..... 3
System Description .................................................. 3
FUNCTION DESCRIPTION .................................. 4
FAIL-SAFE MODE ................................................ 4
CAN Communication System Description ................ 5
CAN Communication Unit ........................................ 5
Schematic ................................................................ 6
Wiring Diagram — PSB — ....................................... 7
Terminals and Reference Value for Pre-Crash Seat
Belt Control Unit ..................................................... 13
Work Flow .............................................................. 13
CONSULT-II Function (PRECRASH SEATBELT) ... 14
CONSULT-II START PROCEDURE .................... 14
HOW TO READ SELF-DIAGNOSTIC RESULTS ... 14
SELF-DIAGNOSTIC RESULTS ITEM CHART ... 14
DATA MONITOR ITEM CHART .......................... 14
Preliminary Check .................................................. 15
PRE-CRASH SEAT BELT OPERATION
INSPECTION ...................................................... 15
Diagnoses Symptom Chart .................................... 15
Check CAN Communication Circuit [U1000] .......... 15
Check Ignition Power Supply Circuit ...................... 16
Check Motor Power Supply and Ground Circuit
[B2454] ................................................................... 16
Check Seat Belt Buckle Switch (Driver Side) Circuit ... 18
Check Seat Belt Buckle Switch (Passenger Side)
Circuit ..................................................................... 20
Check Brake Pedal Stroke Sensor Circuit [B2453] ... 21
Check Pre-Crash Seat Belt Motor LH Circuit [B2452]
... 24
Check Pre-Crash Seat Belt Motor RH Circuit
[B2451] ................................................................... 26Check Brake Pedal Stroke Sensor Shield Wire Cir-
cuit .......................................................................... 27
Removal and Installation of Pre-Crash Seat Belt
Control Unit ............................................................. 28
REMOVAL ........................................................... 28
INSTALLATION ................................................... 28
SEAT BELTS ............................................................. 29
System Description ................................................. 29
SEAT BELT WARNING CHIME ........................... 29
SEAT BELT WARNING LAMP ............................. 29
Removal and Installation of Front Seat Belt ........... 29
REMOVAL OF SEAT BELT RETRACTOR .......... 29
INSTALLATION OF SEAT BELT RETRACTOR ... 30
REMOVAL OF SEAT BELT BUCKLE .................. 30
INSTALLATION OF SEAT BELT BUCKLE .......... 30
Removal and Installation of Rear Seat Belt ............ 31
REMOVAL OF SEAT BELT RETRACTOR .......... 31
INSTALLATION OF SEAT BELT RETRACTOR ... 31
REMOVAL OF SEAT BELT BUCKLE .................. 31
INSTALLATION OF SEAT BELT BUCKLE .......... 32
Seat Belt Inspection ................................................ 32
AFTER A COLLISION ......................................... 32
PRELIMINARY CHECKS .................................... 32
SEAT BELT RETRACTOR ON-VEHICLE
CHECK ................................................................ 33
SEAT BELT RETRACTOR OFF-VEHICLE
CHECK (FRONT SEAT BELT) ............................ 34
SEAT BELT RETRACTOR OFF-VEHICLE
CHECK (REAR SEAT BELT) ............................... 34
LATCH (LOWER ANCHORS AND TETHER FOR
CHILDREN) SYSTEM ............................................... 35
Removal and Installation ........................................ 35
REMOVAL ........................................................... 35
INSTALLATION ................................................... 35
TOP TETHER STRAP CHILD RESTRAINT ............. 36
Removal and Installation ........................................ 36
REMOVAL ........................................................... 36
INSTALLATION ................................................... 36

PRE-CRASH SEAT BELT
SB-3
C
D
E
F
G
I
J
K
L
MA
B
SB
Revision: 2007 April2007 M35/M45
PRE-CRASH SEAT BELTPFP:98845
Component Parts and Harness Connector LocationNHS0007X
System DescriptionNHS0007Y

Pre-crash seat belt system is adapted to front seat belts RH/LH.

When the pre-crash seat belt control unit judges the emergency braking operation, it gives the sense of
security by the motor built into the pre-crash seat belt retracting the shoulder belt and suppressing the
crew's posture change. Also, it eases the damage of the collision.
PHIA1123E
1. Fuse block (J/B) 2.Fuse, fusible link and relay block
(J/B)3.Pre-crash seat belt control unit B142
(View with the trunk side finisher LH
removed)
4.Brake pedal stroke sensor E125
(View with the instrument driver
lower panel removed)5.Pre-crash seat belt motor B32 (LH),
B422 (RH)
(View with the center pillar lower
garnish removed)6.Seat belt buckle switch B203 (driver
seat) B253 (passenger seat)

PRE-CRASH SEAT BELT
SB-5
C
D
E
F
G
I
J
K
L
MA
B
SB
Revision: 2007 April2007 M35/M45
CAN Communication System DescriptionNHS0007Z
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 UnitNHS00080
Refer to LAN-50, "CAN System Specification Chart" .

PRE-CRASH SEAT BELT
SB-13
C
D
E
F
G
I
J
K
L
MA
B
SB
Revision: 2007 April2007 M35/M45
Terminals and Reference Value for Pre-Crash Seat Belt Control UnitNHS00083
Work FlowNHS00084
1. Check the symptom and customer's requests.
2. Understand the system description. Refer to SB-3, "
System Description" .
3. Perform the preliminary check. Refer to SB-15, "
Preliminary Check" .
4. Check the self-diagnosis, results using CONSULT-II. Refer to SB-14, "
CONSULT-II Function (PRECRASH
SEATBELT)" .
5. Based on the trouble diagnosis chart, repair or replace the cause of the malfunction. Refer to SB-15,
"Diagnoses Symptom Chart" .
6. Does pre-crash seat belt system operate normally?
OK: GO TO 7.
NG: GO TO 4.
7. INSPECTION END
TerminalWire
ColorItemSignal
Input/OutputConditionVo l ta g e [V ]
(Approx.)
1G/RSeat belt motor RH release
direction signalOutputSeat belt motor RH operation Battery voltage
Other than above 0
2 W Power source (BAT) Input — Battery voltage
3G/YSeat belt motor RH fastened
direction signalOutputSeat belt motor RH operation Battery voltage
Other than above 0
4GY/WSeat belt motor LH fastened
direction signalOutputSeat belt motor LH operation Battery voltage
Other than above 0
5 B/Y Ground (Driver circuit) — — 0
6L/YSeat belt motor LH release
direction signalOutputSeat belt motor LH operation Battery voltage
Other than above 0
7 G/Y Seat belt indicator signal OutputWhen driver side seat belt is fastened Battery voltage
When driver side seat belt is un-fastened 0
When driver side seat belt is fastened and
system malfunctionBattery
voltage ⇔ 0
8 LG Seat belt buckle switch RH InputWhen seat belt is fastened 5
When seat belt is un-fastened 0
10 SB Seat belt buckle switch LH InputWhen seat belt is fastened Battery voltage
When seat belt is un-fastened 0
13 W/G Power source (IGN) Input Ignition switch ON or START Battery voltage
16 WBrake pedal stroke sensor
output signal 1OutputBrake pedal is fully released operation 1
Brake pedal is slightly depressed operation 4
18 RPower source
(Brake pedal stroke sensor)Input — 5
20 GBrake pedal stroke sensor
output signal 2OutputBrake pedal is fully released operation 4
Brake pedal is slightly depressed operation 1
21 BGround
(Brake pedal stroke sensor)—— 0
22 P CAN-L Input/Output — —
24 L CAN-H Input/Output — —
25 — Ground (Shield wire) — — 0
26 B/Y Ground (Control circuit) — — 0

SB-14
PRE-CRASH SEAT BELT
Revision: 2007 April2007 M35/M45
CONSULT-II Function (PRECRASH SEATBELT)NHS00085
CONSULT-II can display each diagnostic item using the diagnostic test modes shown following.
CONSULT-II START PROCEDURE
Refer to GI-38, "CONSULT-II Start Procedure" .
HOW TO READ SELF-DIAGNOSTIC RESULTS
SELF-DIAGNOSTIC RESULTS ITEM CHART
DATA MONITOR ITEM CHART
CONSULT-II
diagnosis itemsInspection item
self-diagnosis modeContentReference
page
PRECRASH
SEATBELTSELF–DIAG RESULTS Carries out the self-diagnosis.SB-14
DATA MONITOR Displays pre-crash seat belt control unit input data in real time.SB-14
CAN DIAG SUPPORT MNTRThe results of transmit / receive diagnosis of CAN communication
can be read.LAN-44
ECU PART NUMBER Displays pre-crash seat belt control unit part No. —
PHIA1176E
DTCSelf-diagnosis item
(CONSULT-II indication)DTC detection conditionReference
page
U1000 CAN COMM CIRCUITWhen pre-crash seat belt control unit is not transmitting or receiving CAN
communication signal for 2 seconds or more. SB-15
B2451 SB MOTOR RH CIRC Circuit of seat belt motor (RH) is open or shorted.SB-26
B2452 SB MOTOR LH CIRC Circuit of seat belt motor (LH) is open or shorted.SB-24
B2453 BR STROKE SEN CIRC Circuit of brake pedal stroke sensor is open or shorted.SB-21
B2454 MOTOR PWR SUP CIRC Circuit of motor power supply is open or shorted.SB-16
B2455 PSB C/U INT CIRC ECU circuit internal abnormality —
Monitor item [OPERATION or UNIT] Contents
SB SW RH SIG “ON/OFF” RH seat belt switch signal is displayed.
SB SW LH SIG “ON/OFF” LH seat belt switch signal is displayed.
VHCL SPEED SE “Km/h” Vehicle speed signal is displayed.
B PEDAL SIG1 “V” Brake pedal stroke sensor 1 signal voltage is displayed.
B PEDAL SIG 2 “V” Brake pedal stroke sensor 2 signal voltage is displayed.

PRE-CRASH SEAT BELT
SB-15
C
D
E
F
G
I
J
K
L
MA
B
SB
Revision: 2007 April2007 M35/M45
Preliminary CheckNHS00086
PRE-CRASH SEAT BELT OPERATION INSPECTION
WARNING:

The following tests should be performed in a safe, open place that is free of traffic and obstacles.

The tests should be performed on a dry, paved road. Do not attempt the tests on wet or unpaved
road, open road, or highway. (This may cause an accident or personal injury.)

Driver and passenger assume it will not operate and prepare themselves accordingly.
1. Tighten driver and passenger seat belts.
2. Drive at approximately 25 km/h (16 MPH).
3. Notify passenger of a sudden stop. Driver and passenger prepare themselves for the possibility of
system not operating. Then, driver fully depresses the brake pedal to stop suddenly.
4. Make sure that the shoulder of the seat belt is pulled while braking.
Diagnoses Symptom ChartNHS00087
Check CAN Communication Circuit [U1000]NHS00088
1. CHECK SELF-DIAGNOSTIC RESULT
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 carry out CAN communication.
With CONSULT-II
1. Connect CONSULT-II, and turn ignition switch ON.
2. Touch “PRECRASH SEATBELT” on “SELECT SYSTEM”
screen.
3. Touch “SELF-DIAG RESULTS” on “SELECT DIAG MODE”
screen.
4. Check display content in self-diagnostic results.
Displayed U1000?
Ye s > > G O T O LAN-50, "CAN System Specification Chart" .
No >> Inspection END.
Symptom Diagnosis procedureReference
page
All functions of pre-crash seat belt system
does not operate.1. Check ignition power supply circuit SB-16
2. Check motor power supply and ground circuit [B2454]SB-16
3. Check CAN communication circuitSB-15
4. Replace pre-crash seat belt control unitSB-28
Driver side pre-crash seat belt system does
not operate.1. Check seat belt buckle switch (driver side) circuit SB-182. Check pre-crash seat belt motor LH circuit [B2452]SB-24
3. Replace pre-crash seat belt control unitSB-28
Passenger side pre-crash seat belt system
does not operate.1. Check seat belt buckle switch (passenger side) circuit SB-202. Check pre-crash seat belt motor RH circuit [B2451]SB-26
3. Replace pre-crash seat belt control unitSB-28
Pre-crash seat belt system does not operate
during emergency brake operation.1. Check CAN communication circuit [U1000]SB-152. Check brake pedal stroke sensor circuit [B2453]SB-21
3. Check brake pedal stroke sensor shield wire circuit SB-27
4. Replace pre-crash seat belt control unitSB-28
PHIA0772E

SB-16
PRE-CRASH SEAT BELT
Revision: 2007 April2007 M35/M45
Check Ignition Power Supply Circuit NHS00089
1. CHECK FUSE
Check 10A fuse [No.15, located in fuse block (J/B)].
NOTE:
Refer to SB-3, "
Component Parts and Harness Connector Location" .
OK or NG
OK >> GO TO 2.
NG >> If fuse is blown out, be sure to eliminate cause of malfunction before installing new fuse. Refer to
PG-3, "
POWER SUPPLY ROUTING CIRCUIT" .
2. CHECK IGNITION POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect pre-crash seat belt control unit connector.
3. Turn ignition switch ON.
4. Check voltage between pre-crash seat belt control unit harness
connector and ground.
OK or NG
OK >> Ignition power supply circuit is OK.
NG >> Check pre-crash seat belt control unit ignition power supply circuit harness.
Check Motor Power Supply and Ground Circuit [B2454]NHS0008A
1. CHECK FUSE
Check 30A fusible link (letter G , located in the fuse and fusible link box).
NOTE:
Refer to SB-3, "
Component Parts and Harness Connector Location" .
OK or NG
OK >> GO TO 2.
NG >> If fuse is blown out, be sure to eliminate cause of malfunction before installing new fuse. Refer to
PG-3, "
POWER SUPPLY ROUTING CIRCUIT" .
Terminal
Voltage (V)
(Approx.) (+)
(–) Pre-crash seat
belt control unit
connectorTerminal
B142 13 Ground Battery voltage
PHIA1126E

PRE-CRASH SEAT BELT
SB-17
C
D
E
F
G
I
J
K
L
MA
B
SB
Revision: 2007 April2007 M35/M45
2. CHECK SELF-DIAGNOSTIC RESULT
With CONSULT-II
Select “SELF-DIAG RESULTS” and then make sure the “MOTOR
PWR SUP CIRC” is displayed.
Without CONSULT-II
When CONSULT-II is not used, omit this inspection, and then GO TO 3.
Displayed B2454?
Ye s > > G O T O 3 .
No >> Motor power supply system is normal.
3. CHECK MOTOR POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect pre-crash seat belt control unit connector.
3. Check voltage between pre-crash seat belt control unit harness
connector and ground.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness.
4. CHECK PRE-CRASH SEAT BELT CONTROL UNIT GROUND CIRCUIT
1. Disconnect pre-crash seat belt control unit connector.
2. Check continuity between pre-crash seat belt control unit har-
ness connector and ground.
OK or NG
OK >> Motor power supply and ground circuit is OK.
NG >> Repair or replace harness.
CONSULT-II display CONSULT-II display code
NO DTC —
MOTOR PWR SUP CIRC B2454
PHIA0770E
Terminal
Voltage (V)
(Approx.) (+)
(–) Pre-crash seat
belt control unit
connectorTerminal
B142 2 Ground Battery voltage
PHIA1127E
Terminal
Continuity Pre-crash seat
belt control unit
connectorTerminal
Ground
B1425
Ye s
26
PHIA1128E