Infiniti Q45. Manual - part 525

IGNITION SIGNAL

EC-739

C

D

E

F

G

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EC

5. 

CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II

1.

Turn ignition switch OFF.

2.

Disconnect condenser harness connector.

3.

Turn ignition switch ON.

4.

Check voltage between condenser terminal 1 and ground with
CONSULT-II or tester.

OK or NG

OK

>> GO TO 11.

NG

>> GO TO 6.

6. 

CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III

1.

Turn ignition switch OFF.

2.

Disconnect ECM relay.

3.

Check harness continuity between ECM relay terminal 3 and
condenser terminal 1.
Refer to Wiring Diagram.

4.

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

OK or NG

OK

>> GO TO 8.

NG

>> GO TO 7.

7. 

DETECT MALFUNCTIONING PART

Check the following.

●

Harness connectors M135, F105

●

Fuse block (J/B) No. 2 harness connector M143

●

Harness for open or short between ECM relay and condenser

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

PBIB2425E

Voltage: Battery voltage

PBIB0624E

Continuity should exist.

PBIB0040E

EC-740

IGNITION SIGNAL

8. 

CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV

Check voltage between ECM relay terminal 5 and ground with CON-
SULT-II or tester.

OK or NG

OK

>> GO TO 10.

NG

>> GO TO 9.

9. 

DETECT MALFUNCTIONING PART

Check the following.

●

20A fuse

●

Fuse, fusible link and relay block (J/B) harness connector E3

●

Fuse block (J/B) No. 2 harness connector E215

●

Harness for open and short between ECM relay and fuse

>> Repair or replace harness or connectors.

10. 

CHECK ECM RELAY

Refer to 

EC-155, "Component Inspection"

 .

OK or NG

OK

>> GO TO 18.

NG

>> Replace ECM relay.

11. 

CHECK CONDENSER CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Disconnect condenser harness connector.

3.

Check harness continuity between condenser terminal 2 and ground.
Refer to Wiring Diagram.

4.

Also check harness for short to power.

OK or NG

OK

>> GO TO 12.

NG

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

12. 

CHECK CONDENSER

Refer to 

EC-742, "Component Inspection"

OK or NG

OK

>> GO TO 13.

NG

>> Replace condenser.

Voltage: Battery voltage

PBIB2078E

Continuity should exist.

IGNITION SIGNAL

EC-741

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M

A

EC

13. 

CHECK IGNITION COIL POWER SUPPLY CIRCUIT-V

1.

Reconnect all harness connectors disconnected.

2.

Disconnect ignition coil harness connector.

3.

Turn ignition switch ON.

4.

Check voltage between ignition coil terminal 3 and ground with
CONSULT-II or tester.

OK or NG

OK

>> GO TO 15.

NG

>> GO TO 14.

14. 

DETECT MALFUNCTIONING PART

Check the harness for open or short between ignition coil and ECM relay.

>> Repair or replace harness or connectors.

15. 

CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Check harness continuity between ignition coil terminal 2 and ground.
Refer to Wiring Diagram.

3.

Also check harness for short to power.

OK or NG

OK

>> GO TO 16.

NG

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

16. 

CHECK IGNITION COIL OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Disconnect ECM harness connector.

2.

Check harness continuity between ECM terminals 46, 60, 61, 62, 65, 79, 80, 81 and ignition coil terminal
1. Refer to Wiring Diagram.

3.

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

OK or NG

OK

>> GO TO 17.

NG

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

Voltage: Battery voltage

PBIB2424E

PBIB0138E

Continuity should exist.

Continuity should exist.

EC-742

IGNITION SIGNAL

17. 

CHECK IGNITION COIL WITH POWER TRANSISTOR

Refer to 

EC-742, "Component Inspection"

 .

OK or NG

OK

>> GO TO 18.

NG

>> Replace ignition coil with power transistor.

18. 

CHECK INTERMITTENT INCIDENT

Refer to 

EC-145, "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT"

 .

>> INSPECTION END

Component Inspection

NBS00272

IGNITION COIL WITH POWER TRANSISTOR

CAUTION:

Do the following procedure in the place where ventilation is good without the combustible.

1.

Turn ignition switch OFF.

2.

Disconnect ignition coil harness connector.

3.

Check resistance between ignition coil terminals as follows.

4.

If NG, replace ignition coil with power transistor.
If OK, go to next step.

5.

Turn ignition switch OFF.

6.

Reconnect all harness connectors disconnected.

7.

Remove fuel pump fuse in fuse block No. 1 to release fuel pres-
sure.
NOTE:
Do not use CONSULT-II to release fuel pressure, or fuel pres-
sure applies again during the following procedure.

8.

Start engine.

9.

After engine stalls, crank it two or three times to release all fuel
pressure.

10. Turn ignition switch OFF.
11. Remove all ignition coil harness connectors to avoid the electri-

cal discharge from the ignition coils.

12. Remove ignition coil and spark plug of the cylinder to be checked.

13. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.

14. Connect spark plug and harness connector to ignition coil.

15. Fix ignition coil using a rope etc. with gap of 13 - 17 mm

between the edge of the spark plug and grounded metal portion
as shown in the figure.

16. Crank engine for about 3 seconds, and check whether spark is

generated between the spark plug and the grounded metal por-
tion.

Terminal No. (Polarity)

Resistance 

Ω

 [at 25

°

C (77

°

F)]

1 and 2

Except 0 or 

∞

1 and 3

Except 0

2 and 3

Spark should be generated.

PBIB0847E

PBIB0041E

PBIB2325E