Infiniti G37 Coupe. Manual - part 658

EXL-52

< COMPONENT DIAGNOSIS >

[XENON TYPE]

B2519 LEVELIZER CALIBRATION

B2519 LEVELIZER CALIBRATION

Description

INFOID:0000000001604633

AFS control unit transmits the height sensor signal from the height sensor.

DTC Logic

INFOID:0000000001604634

[B2519] Levelizer calibration

Diagnosis Procedure

INFOID:0000000001604635

1.

LEVELIZER ADJUSTMENT

Perform the levelizer adjustment.

>> Refer to 

EXL-7, "LEVELIZER ADJUSTMENT : Special Repair Requirement"

.

DTC detection condition

DTC erase condition

Possible causes

The height sensor adjustment position is not recognized.

When the levelizer adjust-
ment is completed

AFS control unit

B2521 ECU CIRCUIT

EXL-53

< COMPONENT DIAGNOSIS >

[XENON TYPE]

C

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EXL

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B2521 ECU CIRCUIT

Description

INFOID:0000000001604636

AFS control unit judges the vehicle condition from each signal. AFS control unit controls AFS function and the
headlamp aiming.

DTC Logic

INFOID:0000000001604637

DTC DETECTION LOGIC

[B2521] ECU circuit

DTC CONFIRMATION PROCEDURE

1.

DTC ERASE

Erase the DTC memory of AFS with CONSULT-III.

>> GO TO 2.

2.

DTC CONFIRMATION PROCEDURE

1.

Turn ignition ON.

2.

Select the self-diagnosis with CONSULT-III.

Is “B2521” detected?

YES

>> Refer to 

EXL-53, "Diagnosis Procedure"

.

NO

>> Refer to 

GI-38, "Intermittent Incident"

.

Diagnosis Procedure

INFOID:0000000001604638

1.

CHECK EACH SENSOR POWER SUPPLY

1.

Turn the ignition switch ON.

2.

Check the voltage between the AFS control unit harness connector and the ground.

Is the measurement value within the standard value?

YES

>> GO TO 2.

Less than the standard value >>GO TO 3.
Higher than the standard value>>GO TO 4.

Error detection condition

DTC erase condition

Possible cause

• AFS control unit indicates an applicable DTC when de-

tecting any of the following conditions continuously for 2 
seconds or more. 

- The swivel position sensor is shorted to the power supply 

or the ground.

- The swivel position sensor signal is shorted to the 

ground.

- The height sensor power supply is shorted to the power 

supply or the ground.

- The height sensor signal is shorted to the ground.
• AFS control unit RAM/ROM error

Ignition switch OFF

Swivel position sensor
• Swivel position sensor
• Harness and connector
• AFS  control  unit
Height sensor
• Height sensor
• Harness and connector
• AFS  control  unit
AFS control unit (RAM/ROM)
• AFS  control  unit

Terminals

Voltage

(Approx.)

(+)

(

−

)

AFS control unit

Ground

Connector

Terminal

M16

4

4 - 6 V

6

24

EXL-54

< COMPONENT DIAGNOSIS >

[XENON TYPE]

B2521 ECU CIRCUIT

2.

CHECK EACH SENSOR SIGNAL

Check the voltage between the AFS control unit harness connector and the ground.

Is the measurement value within the standard value?

YES

>> Replace AFS control unit.

Less than the standard value >>GO TO 5.
Higher than the standard value>>GO TO 6.

3.

CHECK EACH SENSOR POWER SUPPLY SHORT CIRCUIT 

1.

Turn the ignition switch OFF.

2.

Disconnect AFS control unit connector. 

3.

Check continuity between the AFS control unit harness connector and the ground.

Does continuity exist?

YES

>> Repair the harnesses or connectors.

NO

>> Replace AFS control unit.

4.

CHECK EACH SENSOR POWER SUPPLY CIRCUIT 

1.

Turn the ignition switch OFF.

2.

Disconnect AFS control unit connector. 

3.

Check the voltage between the AFS control unit harness connector and the ground.

Is the measurement value normal?

YES

>> Replace AFS control unit.

NO

>> Repair the harnesses or connectors.

5.

CHECK EACH SENSOR SIGNAL SHORT CIRCUIT

1.

Turn the ignition switch OFF.

2.

Disconnect AFS control unit connector. 

3.

Check continuity between the AFS control unit harness connector and the ground.

Terminals

Voltage

(Approx.)

(+)

(

−

)

AFS control unit

Ground

Connector

Terminal

M16

9

0.25 - 4.75 V

28

29

Terminals

Continuity

(+)

(

−

)

AFS control unit

Ground

Connector

Terminal

M16

4

Not existed

6

24

Terminals

Voltage

(Approx.)

(+)

(

−

)

AFS control unit

Ground

Connector

Terminal

M16

4

0 V

6

24

B2521 ECU CIRCUIT

EXL-55

< COMPONENT DIAGNOSIS >

[XENON TYPE]

C

D

E

F

G

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K

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A

B

EXL

N

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Does continuity exist?

YES

>> Repair the harnesses or connectors.

NO

>> Replace AFS control unit.

6.

CHECK EACH SENSOR SIGNAL SHORT CIRCUIT

1.

Turn the ignition switch OFF.

2.

Disconnect AFS control unit connector. 

3.

Turn the ignition switch ON.

4.

Check the voltage between the AFS control unit harness connector and the ground.

Is the measurement value normal?

YES

>> Replace AFS control unit.

NO

>> Repair the harnesses or connectors.

Terminals

Continuity

(+)

(

−

)

AFS control unit

Ground

Connector

Terminal

M16

9

Not existed

28

29

Terminals

Voltage

(Approx.)

(+)

(

−

)

AFS control unit

Ground

Connector

Terminal

M16

9

0 V

28

29