Infiniti FX35, FX50 (S51). Manual - part 1934

POWER SUPPLY AND GROUND CIRCUIT

WT-39

< DTC/CIRCUIT DIAGNOSIS >

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POWER SUPPLY AND GROUND CIRCUIT

Description

INFOID:0000000005549639

Supply power to the low tire pressure warning control unit.

Component Function Check

INFOID:0000000005549640

1.

CHECK THE ILLUMINATION OF THE TIRE PRESSURE WARNING LAMP

Check that the low tire pressure warning lamp is turned OFF after illuminating for approximately 1 second,
when the ignition switch is turned ON.
Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Perform trouble diagnosis. Refer to 

WT-39, "Diagnosis Procedure"

. 

Diagnosis Procedure

INFOID:0000000005549641

1.

CHECK FUSE/FUSIBLE LINK

Check for fusing of the fuse and fusible link at the low tire pressure warning control unit.
• Check the 10 A fuse [No. 3 inside the fuse block (J/B)]

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace error-detected parts.

2.

POWER SUPPLY SYSTEM CHECK

1.

Turn the ignition switch OFF.

2.

Disconnect the low tire pressure warning control unit harness connector.

3.

Turn the ignition switch ON.

CAUTION:

Never start engine.

4.

Check the continuity between the low tire pressure warning control unit harness connector and the
ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair or replace error-detected parts.

3.

GROUND SYSTEM INSPECTION

1.

Turn the ignition switch OFF.

2.

Check the continuity between the low tire pressure warning control unit harness connector and the
ground.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace error-detected parts.

4.

CHECK TIRE PRESSURE RECEIVER POWER SUPPLY CIRCUIT

1.

Connect the low tire pressure warning control unit harness connector.

2.

Disconnect the tire pressure receiver harness connector.

3.

Check the voltage between the tire pressure receiver harness connector and ground.

Low tire pressure warning control unit

—

Voltage

Connector

Terminal

M96

15

Ground

Battery voltage

Low tire pressure warning control unit

—

Continuity

Connector

Terminal

M96

32

Ground

Existed

WT-40

< DTC/CIRCUIT DIAGNOSIS >

POWER SUPPLY AND GROUND CIRCUIT

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair or replace error-detected parts.

5.

CHECK RECEIVER GROUND CIRCUIT

1.

Disconnect the low tire pressure warning control unit harness connector. 

2.

Check the continuity between the harness connector terminals of the receiver and the low tire pressure
warning control unit.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Repair or replace error-detected parts.

Tire pressure receiver

—

Voltage

Connector

Terminal

E53 (Front LH)

1

Ground

7 - 16 V

E19 (Front RH)

B43 (Rear LH)

B251 (Rear RH)

Tire pressure receiver

Low tire pressure warning control unit

Continuity

Connector

Terminal

Connector

Terminal

E53 (Front LH)

4

M96

26

Existed

E19 (Front RH)

25

B43 (Rear LH)

24

B251 (Rear RH)

23

TIRE PRESSURE WARNING CHECK SWITCH

WT-41

< DTC/CIRCUIT DIAGNOSIS >

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TIRE PRESSURE WARNING CHECK SWITCH

Description

INFOID:0000000005549642

The following item can be checked by grounding the tire pressure warning check switch harness connector
terminal.

Component Function Check

INFOID:0000000005549643

1.

CHECK LOW TIRE PRESSURE WARNING LAMP OPERATION

Check if low tire pressure warning lamp blinks 1 second and then goes off after turning ignition switch ON.
Is inspection result normal?

YES

>> GO TO 2.

NO

>> Check low tire pressure warning lamp. Refer to 

WT-43, "Diagnosis Procedure"

.

2.

CHECK TIRE PRESSURE WARNING CHECK SWITCH OPERATION

1.

Ground the tire pressure warning check switch harness connector terminal.

2.

Check the low tire pressure warning lamp blinks.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Proceed to trouble diagnosis procedure. Refer to 

WT-41, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000005549644

1.

CHECK TIRE PRESSURE WARNING CHECK SWITCH POWER SUPPLY CIRCUIT

1.

Turn the ignition switch ON.

CAUTION:

Never start the engine.

2.

Check the voltage between tire pressure warning check switch connector and ground.

Is the inspection result normal?

YES

>> Repair or replace low tire pressure warning control unit. Replace low tire pressure warning control

unit. Refer to 

WT-76, "Exploded View"

.

NO

>> GO TO 2.

2.

CHECK TIRE PRESSURE WARNING CHECK SWITCH CIRCUIT

1.

Turn the ignition switch OFF.

2.

Disconnect low tire pressure warning control unit harness connector

3.

Check the continuity between low tire pressure warning control unit harness connector and tire pressure
warning check switch connector.

4.

Check the continuity between low tire pressure warning control unit harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair or replace error-detected parts.

Tire pressure warning check switch

—

Voltage

Connector

Terminal

M23

1

Ground

7.6 - 14.6 V

Low tire pressure warning control unit

Tire pressure warning check switch

Continuity

Connector

Terminal

Connector

Terminal

Existed

M96

12

M23

1

Low tire pressure warning control unit

—

Continuity

Connector

Terminal

M96

12

Ground

Not existed

WT-42

< DTC/CIRCUIT DIAGNOSIS >

TIRE PRESSURE WARNING CHECK SWITCH

3.

CHECK LOW TIRE PRESSURE WARNING CONTROL UNIT

Check the low tire pressure warning control unit input/output signal. Refer to 

WT-45, "Reference Value"

.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Check low tire pressure warning control unit pin terminals for damage or loose connection with

harness connector. If any items are damaged, repair or replace damaged parts. Replace low tire
pressure warning control unit. Refer to 

WT-76, "Exploded View"

.