Infiniti Q45. Manual - part 787

PRE-CRASH SEAT BELT

SB-27

C

D

E

F

G

I

J

K

L

M

A

B

SB

Check Seat Belt Buckle Switch (Driver Side) Circuit 

NHS0003Z

1. 

CHECK PRE-CRASH SEAT BELT CONTROL UNIT INPUT SIGNAL

 With CONSULT-II

Select “SB SW LH SIG” on DATA MONITOR screen, and then make sure that ON/OFF display changes syn-
chronized with the insertion operation to the seat belt buckle.

Without CONSULT-II

1.

Turn the ignition switch ON.

2.

Check voltage between seat belt buckle switch (driver side) har-
ness connector and ground.

OK or NG

OK

>> Seat belt buckle switch (driver side) circuit is OK.

NG

>> GO TO 2.

2. 

CHECK SEAT BELT BUCKLE SWITCH (DRIVER SIDE) HARNESS

1.

Turn the ignition switch OFF.

2.

Disconnect pre-crash seat belt control unit connector.

3.

Check continuity between pre-crash seat belt control unit har-
ness connector B318 terminal 10 and seat belt buckle switch
(driver side) harness connector B150 terminal 41.

4.

Check continuity between pre-crash seat belt control unit har-
ness connector B318 terminal 10 and ground.

OK or NG

OK

>> GO TO 3.

NG

>> Repair or replace harness.

SB SW LH SIG

When passenger seat belt is not fastened

: OFF

When passenger seat belt is fastened

: ON

PHIA0765E

Connector

Terminal

Condition

Voltage [V]

(Approx.)

(+)

(–)

B150

41 (L/B)

Ground

When seat belt is not fastened

0

When seat belt is fastened

5

PHIA0746E

10 (G/W) - 41 (L/B)

: Continuity should exist.

10 (G/W) - Ground

: Continuity should not exist.

PHIA0747E

SB-28

PRE-CRASH SEAT BELT

3. 

CHECK LH SEAT BELT SWITCH

Check continuity between seat belt buckle switch (driver side) B150
terminals 41 and 15A while performing the insertion operation to the
seat belt buckle.

OK or NG

OK

>> GO TO 4.

NG

>> Replace seat belt buckle switch (driver side).

4. 

CHECK LH SEAT BELT SWITCH GROUND CIRCUIT HARNNES

Check continuity between seat belt buckle switch (driver side) har-
ness connector B150 terminal 15A and ground.

OK or NG

OK

>> Check harness connection.

●

If it is OK, replace pre-crash seat belt control unit.

●

If it is NG, repair or replace malfunction part.

NG

>> Repair or replace harness.

Check Seat Belt Buckle Switch (Passenger Side) Circuit 

NHS00040

1. 

CHECK PRE-CRASH SEAT BELT CONTROL UNIT INPUT SIGNAL

 With CONSULT-II

Select “SB SW RH SIG” on DATA MONITOR screen, and then make
sure that ON/OFF display changes synchronized with the insertion
operation to the seat belt buckle.

 Without CONSULT-II

1.

Turn the ignition switch ON.

2.

Check voltage between seat belt buckle switch (passenger side)
harness connector and ground.

OK or NG

OK

>> Seat belt buckle switch (passenger side) circuit is OK.

NG

>> GO TO 2.

Connector

Terminal

Condition

Continuity 

B150

41 15A

When seat belt is not fastened

 Yes

When seat belt is fastened

No

PHIA0748E

15A (B) - Ground

: Continuity should not exist.

PHIA0749E

SB SW RH SIG

When RH seat belt is not fastened

:OFF

When RH seat belt is fastened

:ON

PHIA0764E

Connector

Terminal

(Wire color)

Condition

Voltage [V]

(Approx.)

(+)

(–)

B350

41 (SB)

Ground

When seat belt is not fastened

0

When seat belt is fastened

5

PHIA0746E

PRE-CRASH SEAT BELT

SB-29

C

D

E

F

G

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J

K

L

M

A

B

SB

2. 

CHECK SEAT BELT BUCKLE SWITCH (PASSENGER SIDE) HARNESS

1.

Turn ignition switch OFF.

2.

Disconnect pre-crash seat belt control unit connector.

3.

Check continuity between pre-crash seat belt control unit har-
ness connector B318 terminal 8 and seat belt buckle switch
(passenger side) harness connector B350 terminal 41.

4.

Check continuity between pre-crash seat belt control unit har-
ness connector B318 terminal 8 and ground.

OK or NG

OK

>> GO TO 3.

NG

>> Repair or replace harness.

3. 

CHECK RH SEAT BELT SWITCH

Check continuity between seat belt buckle switch (passenger side)
B350 terminals 41 and 14 while performing the insertion operation to
the seat belt buckle.

OK or NG

OK

>> GO TO 4.

NG

>> Replace seat belt buckle (passenger side).

4. 

CHECK RH SEAT BELT SWITCH GROUND CIRCUIT HARNNES

Check continuity between seat belt buckle switch (passenger side)
harness connector B350 terminal 14 and ground.

OK or NG

OK

>> Check harness connection.

●

If it is OK, replace pre-crash seat belt control unit.

●

If it is NG, repair or replace malfunction part.

NG

>> Repair or replace harness.

8 (SB) - 41 (SB)

: Continuity should exist.

8 (SB) - Ground

: Continuity should not exist.

PHIA0750E

Connector

Terminal

Condition

Continuity 

B350

41 14

When seat belt is not fastened

 Yes

When seat belt is fastened

No

PHIA0751E

14 (B) - Ground

: Continuity should exist.

PHIA0752E

SB-30

PRE-CRASH SEAT BELT

Check Brake Pedal Stroke Sensor Circuit [B2453]

NHS00041

1. 

INSPECTION WITH CONSULT-II

 With CONSULT-II

Select “SELF-DIAG RESULTS”, and then make sure that “BR
STROKE SEN CIRC” is displayed.

Without CONSULT-II

When CONSULT-II is not used, omit this inspection, and then GO TO 2.

Displayed B2453?

Yes

>> GO TO 3.

No

>> GO TO 2.

2. 

CHECK PRE-CRASH SEAT BELT CONTOROL UNIT INPUT SIGNAL

 With CONSULT-II

Select “B PEDAL SIG1” and “B PEDAL SIG2”, and then make sure that the voltage changes synchronized
with brake pedal operation.

 Without CONSULT-II

1.

Turn the ignition switch ON.

2.

Check voltage between pre-crash seat belt control unit harness
connector and ground.

OK or NG

OK

>> Brake pedal stroke sensor system is normal.

NG

>> GO TO 3.

CONSULT-II display

CONSULT-II display code

NO DTC

–

BR STROKE SEN CIRC

B2453

PHIA0769E

B PEDAL SIG1

Brake released 

→

 depressed

: Approx. 1 

→

 4V

B PEDAL SIG 2

Brake released 

→

 depressed

: Approx. 4 

→

 1V

PHIA0766E

Connector

Terminal

(Wire color)

Condition

Voltage [V]

(Approx.)

(+)

(–)

B318

16 (W)

Ground

Brake released 

→

depressed

1 

→

 4

20 (G)

4 

→

 1

PHIA0753E