Infiniti QX56 (Z62). Manual - part 632

EC-506

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

IGNITION SIGNAL

IGNITION SIGNAL

Component Function Check

INFOID:0000000006218011

1.

INSPECTION START

Turn ignition switch OFF, and restart engine.
Does the engine start?

YES-1 >> With CONSULT-III: GO TO 2.
YES-2 >> Without CONSULT-III: GO TO 3.
NO

>> Go to 

EC-506, "Diagnosis Procedure"

.

2.

CHECK IGNITION SIGNAL FUNCTION

 WITH CONSULT-III

1.

Perform “POWER BALANCE” in “ACTIVE TEST” mode with CONSULT-III.

2.

Check that each circuit produces a momentary engine speed drop.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Go to 

EC-506, "Diagnosis Procedure"

.

3.

CHECK IGNITION SIGNAL FUNCTION

 WITHOUT CONSULT-III

1.

Let engine idle.

2.

Read the voltage signal between ECM harness connector terminals under the following conditions with an
oscilloscope.

NOTE:

The pulse cycle changes depending on rpm at idle.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Go to 

EC-506, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000006218012

1.

CHECK IGNITION COIL POWER SUPPLY CIRCUIT-I

1.

Turn ignition switch OFF, wait at least 10 seconds and then turn it ON.

2.

Check the voltage between ECM harness connector terminals under the following conditions.

ECM

Voltage signal

Cylinder

+

–

Connector

Terminal

Connector

Terminal

1

F111

12

E80

175

2

13

3

14

4

15

5

17

6

18

7

19

8

20

PBIB0044E

IGNITION SIGNAL

EC-507

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Go to 

EC-168, "Diagnosis Procedure"

.

2.

CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II

1.

Turn ignition switch OFF.

2.

Disconnect condenser harness connector.

3.

Turn ignition switch ON.

4.

Check the voltage between condenser harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> GO TO 3.

3.

CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III

1.

Turn ignition switch OFF.

2.

Disconnect IPDM E/R harness connector E7.

3.

Check the continuity between IPDM E/R harness connector and condenser harness connector.

4.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> Go to 

EC-168, "Diagnosis Procedure"

.

NO

>> GO TO 4.

4.

DETECT MALFUNCTIONING PART

Check the following.
• Harness for open or short between IPDM E/R and condenser
• Loose or poor connection for each connector and harness

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

5.

CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Check the continuity between condenser harness connector and ground.

3.

Also check harness for short to power.

Is the inspection result normal?

ECM

Voltage

Connector

+

–

Terminal

Terminal

E80

171

175

Battery voltage

172

Condenser

Ground

Voltage

Connector

Terminal

F8

1

Ground

Battery voltage

IPDM E/R

Condenser

Continuity

Connector

Terminal

Connector

Terminal

E15

61

F8

1

Existed

Condenser

Ground

Continuity

Connector

Terminal

F8

2

Ground

Existed

EC-508

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

IGNITION SIGNAL

YES

>> GO TO 6.

NO

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

6.

CHECK CONDENSER

Refer to 

EC-510, "Component Inspection (Condenser)"

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace condenser.

7.

CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV

1.

Reconnect all harness connectors disconnected.

2.

Disconnect ignition coil harness connector.

3.

Turn ignition switch ON.

4.

Check the voltage between ignition coil harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> GO TO 8.

8.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connector F22 and E46
• Harness for open or short between ignition coil and harness connector F22

>> Repair or replace harness or connectors.

9.

CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Check the continuity between ignition coil harness connector and ground.

3.

Also check harness for short to power.

Is the inspection result normal?

Ignition coil

Ground

Voltage

Cylinder

Connector

Terminal

1

F75

3

Ground

Battery voltage

2

F76

3

3

F77

3

4

F78

3

5

F79

3

6

F80

3

7

F81

3

8

F82

3

Ignition coil

Ground

Continuity

Cylinder

Connector

Terminal

1

F75

2

Ground

Existed

2

F76

2

3

F77

2

4

F78

2

5

F79

2

6

F80

2

7

F81

2

8

F82

2

IGNITION SIGNAL

EC-509

< DTC/CIRCUIT DIAGNOSIS >

[VK56VD]

C

D

E

F

G

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EC

N

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O

YES

>> GO TO 10.

NO

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

10.

CHECK IGNITION COIL OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Disconnect ECM harness connector.

2.

Check the continuity between ignition coil harness connector and ECM harness connector.

3.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 11.

NO

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

11.

CHECK IGNITION COIL WITH POWER TRANSISTOR

Refer to 

EC-509, "Component Inspection (Ignition Coil with Power Transistor)"

.

Is the inspection result normal?

YES

>> GO TO 12.

NO

>> Replace malfunctioning ignition coil with power transistor.

12.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-40, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection (Ignition Coil with Power Transistor)

INFOID:0000000006218013

1.

CHECK IGNITION COIL WITH POWER TRANSISTOR-I

1.

Turn ignition switch OFF.

2.

Disconnect ignition coil harness connector.

3.

Check resistance between ignition coil terminals as per the following.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Replace malfunctioning ignition coil with power transistor.

2.

CHECK IGNITION COIL WITH POWER TRANSISTOR-II

CAUTION:

Perform the following procedure in a place with no combustible objects and good ventilation.
1.

Turn ignition switch OFF.

2.

Reconnect all harness connectors disconnected.

Ignition coil

ECM

Continuity

Cylinder

Connector

Terminal

Connector

Terminal

1

F75

1

F111

12

Existed

2

F76

1

13

3

F77

1

14

4

F78

1

15

5

F79

1

17

6

F80

1

18

7

F81

1

19

8

F82

1

20

Terminals

Resistance [at 25

°

C (77

°

F)]

1 and 2

Except 0 or 

∞

 

Ω

1 and 3

Except 0 

Ω

2 and 3