Infiniti QX56 (Z62). Manual - part 602

EC-386

< DTC/CIRCUIT DIAGNOSIS >

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P1087, P1088 VVEL SYSTEM

P1087, P1088 VVEL SYSTEM

DTC Logic

INFOID:0000000006217892

DTC DETECTION LOGIC

NOTE:
If DTC P1087 or P1088 is displayed with DTC P1090 or P1093.
Perform the trouble diagnosis for DTC P1090 or P1093. Refer to 

EC-390, "DTC Logic"

.

Diagnosis Procedure

INFOID:0000000006217893

If DTC P1087 or P1088 is displayed with DTC P1090 or P1093.
Perform the trouble diagnosis for DTC P1090 or P1093. Refer to 

EC-390, "DTC Logic"

.

DTC No.

Trouble diagnosis name

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P1087

VVEL SYSTEM-B1
[VVEL small event angle malfunction 
(bank 1)]

The event angle of VVEL control 
shaft is always small.

• Harness or connectors

(VVEL actuator motor assembly 
circuit is open or shorted.)

• VVEL actuator motor assembly
• VVEL actuator housing assembly
• VVEL ladder assembly
• VVEL control module

P1088

VVEL SYSTEM-B2
[VVEL small event angle malfunction 
(bank 2)]

P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR

EC-387

< DTC/CIRCUIT DIAGNOSIS >

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P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR

DTC Logic

INFOID:0000000006217894

DTC DETECTION LOGIC

NOTE:
If DTC P1089 or P1092 is displayed with DTC P1608, first perform the trouble diagnosis for DTC P1608.
Refer to 

EC-453, "DTC Logic"

.

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Turn ignition switch OFF and wait at least 10 seconds.

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 10 V or more at idle.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Start engine and let it idle for 1 second.

2.

Check DTC.

Is DTC detected?

YES

>> Go to 

EC-387, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000006217895

1.

VVEL CONTROL SHAFT POSITION SENSOR POWER SUPPLY CIRCUIT

1.

Disconnect VVEL control shaft position sensor harness connector.

2.

Turn ignition switch ON.

3.

Check the voltage between VVEL control shaft position sensor harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 2.

2.

DETECT MALFUNCTIONING PART

Check the following.

DTC No.

Trouble diagnosis name

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P1089

VVEL POS SEN/CIRC-B1
[VVEL control shaft position sen-
sor (bank 1) circuit]

• An excessively low voltage from the sensor 

is sent to VVEL control module.

• An excessively high voltage from the sensor 

is sent to VVEL control module.

• Rationally incorrect voltage is sent to VVEL 

control module compared with the signals 
from VVEL control shaft position sensor 1 
and VVEL control shaft position sensor 2.

• Harness or connectors

(VVEL control shaft position sen-
sor circuit is open or shorted.)

• VVEL control shaft position sen-

sor

• VVEL control module

P1092

VVEL POS SEN/CIRC-B2
[VVEL control shaft position sen-
sor (bank 2) circuit]

DTC No.

VVEL control shaft position sensor

Ground

Voltage (V)

Bank

Connector

Terminal

P1089

1

F72

3

Ground

Approx. 5

6

P1092

2

F70

3

6

EC-388

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR

• Harness for open or short between VVEL control shaft position sensor and VVEL control module
• Loose or poor connection for each connector and harness

>> Repair open circuit, short to ground or short to power in harness or connectors.

3.

CHECK VVEL CONTROL SHAFT POSITION SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Disconnect VVEL control module harness connector.

3.

Check the continuity between VVEL control shaft position sensor harness connector and VVEL control
module harness connector.

4.

Also check harness for short to ground and power.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> GO TO 4.

4.

DETECT MALFUNCTIONING PART

Check the following.
• Harness for open or short between VVEL control shaft position sensor and VVEL control module
• Loose or poor connection for each connector and harness

>> Repair open circuit, short to ground or short to power in harness or connectors.

5.

VVEL CONTROL SHAFT POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Check the continuity between VVEL control shaft position sensor harness connector and VVEL control
module harness connector.

2.

Also check harness for short to ground and power.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> GO TO 6.

6.

DETECT MALFUNCTIONING PART

Check the following.
• Harness for open or short between VVEL control shaft position sensor and VVEL control module
• Loose or poor connection for each connector and harness

>> Repair open circuit, short to ground or short to power in harness or connectors.

7.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-40, "Intermittent Incident"

.

DTC No.

VVEL control shaft position sensor

VVEL control module

Continuity

Bank

Connector

Terminal

Connector

Terminal

P1089

1

F72

2

F56

6

Existed

5

19

P1092

2

F70

2

4

5

17

DTC No.

VVEL control shaft position sensor

VVEL control module

Continuity

Bank

Connector

Terminal

Connector

Terminal

P1089

1

F72

1

F56

3

Existed

4

16

P1092

2

F70

1

5

4

18

P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR

EC-389

< DTC/CIRCUIT DIAGNOSIS >

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Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Repair or replace.

8.

REPLACE VVEL CONTROL MODULE

1.

Replace VVEL control module.

2.

Perform additional service when replacing VVEL control module. Refer to 

EC-144, "Work Procedure"

.

>> GO TO 9.

9.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON.

2.

Erase DTC.

3.

Perform DTC Confirmation Procedure.
See 

EC-387, "DTC Logic"

.

Is the DTC P1089 or P1092 displayed again?

YES

>> GO TO 10.

NO

>> INSPECTION END

10.

REPLACE VVEL ACTUATOR LADDER ASSEMBLY

Replace VVEL actuator ladder assembly. Refer to 

EM-75, "Removal and Installation"

.

>> INSPECTION END