Infiniti QX56 (Z62). Manual - part 696

EXL-76

< DTC/CIRCUIT DIAGNOSIS >

[XENON TYPE]

B2519 LEVELIZER CALIBRATION

B2519 LEVELIZER CALIBRATION

DTC Logic

INFOID:0000000006213940

Diagnosis Procedure

INFOID:0000000006213941

1.

LEVELIZER ADJUSTMENT

Perform the levelizer adjustment.

>> Refer to 

EXL-61, "LEVELIZER ADJUSTMENT : Special Repair Requirement"

.

DTC No.

Trouble diagnosis name

DTC detection condition

Possible causes

B2519

Levelizer calibration

The height sensor adjustment position is not 
recognized.

AFS control unit

B2521 ECU CIRCUIT

EXL-77

< DTC/CIRCUIT DIAGNOSIS >

[XENON TYPE]

C

D

E

F

G

H

I

J

K

M

A

B

EXL

N

O

P

B2521 ECU CIRCUIT

DTC Logic

INFOID:0000000006213942

DTC DETECTION LOGIC

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.

3.

Check the self-diagnosis result. Refer to 

EXL-39, "DTC Index"

.

Is DTC “B2521” detected?

YES

>> Refer to 

EXL-77, "Diagnosis Procedure"

.

NO

>> Refer to 

GI-40, "Intermittent Incident"

.

Diagnosis Procedure

INFOID:0000000006213943

1.

CHECK EACH SENSOR POWER SUPPLY

1.

Turn ignition switch ON.

2.

Check voltage between AFS control unit harness connector and 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.

2.

CHECK EACH SENSOR SIGNAL

Check voltage between AFS control unit harness connector and ground.

DTC No.

Trouble diagnosis name

Error detection condition

Possible cause

B2512

ECU circuit

• AFS control unit indicates an applicable 

DTC when detecting 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 short-

ed to the power supply or the ground.

- The height sensor signal is shorted to 

the ground.

• AFS control unit RAM/ROM error

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

(+)

(

−

)

Voltage

(Approx.)

AFS control unit

Connector

Terminal

M135

4

Ground

5 V

5

6

24

EXL-78

< DTC/CIRCUIT DIAGNOSIS >

[XENON TYPE]

B2521 ECU CIRCUIT

Is the measurement value within the standard value?

YES

>> Replace AFS control unit. Refer to 

EXL-135, "Removal and Installation"

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 ignition switch OFF.

2.

Disconnect AFS control unit connector. 

3.

Check continuity between AFS control unit harness connector and ground.

Is the inspection result normal?

YES

>> Replace AFS control unit. Refer to 

EXL-135, "Removal and Installation"

NO

>> Repair or replace harness.

4.

CHECK EACH SENSOR POWER SUPPLY SHORT CIRCUIT 

1.

Turn ignition switch OFF.

2.

Disconnect AFS control unit connector. 

3.

Check voltage between AFS control unit harness connector and ground.

Is the inspection result normal?

YES

>> Replace AFS control unit. Refer to 

EXL-135, "Removal and Installation"

NO

>> Repair or replace harness.

5.

CHECK EACH SENSOR SIGNAL SHORT CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect AFS control unit connector. 

3.

Check continuity between AFS control unit harness connector and ground.

(+)

(

−

)

Voltage

(Approx.)

AFS control unit

Connector

Terminal

M135

9

Ground

0.25 - 4.75 V

23

28

29

AFS control unit

Ground

Continuity

Connector

Terminal

M135

4

Not existed

5

6

24

(+)

(

−

)

Voltage

(Approx.)

AFS control unit

Connector

Terminal

M135

4

Ground

0 V

5

6

24

B2521 ECU CIRCUIT

EXL-79

< DTC/CIRCUIT DIAGNOSIS >

[XENON TYPE]

C

D

E

F

G

H

I

J

K

M

A

B

EXL

N

O

P

Is the inspection result normal?

YES

>> Replace AFS control unit. Refer to 

EXL-135, "Removal and Installation"

NO

>> Repair or replace harness.

6.

CHECK EACH SENSOR SIGNAL SHORT CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect AFS control unit connector. 

3.

Turn ignition switch ON.

4.

Check voltage between AFS control unit harness connector and ground.

Is the inspection result normal?

YES

>> Replace AFS control unit. Refer to 

EXL-135, "Removal and Installation"

NO

>> Repair or replace harness.

AFS control unit

Ground

Continuity

Connector

Terminal

M135

9

Not existed

23

28

29

(+)

(

−

)

Voltage

(Approx.)

AFS control unit

Connector

Terminal

M135

9

Ground

0 V

23

28

29