INFINITI QX56 2007 Factory Service Manual

EC-628
< SERVICE INFORMATION >
IGNITION SIGNAL
TER-
MI-
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NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
111 W / BECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]
• For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]
• More than a few seconds after turning igni-
tion switch OFFBATTERY VOLTAGE
(11 - 14V)
11 9
120BR
BRPower supply for ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)

IGNITION SIGNAL
EC-629
< SERVICE INFORMATION >
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Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
BBWA1871E

EC-630
< SERVICE INFORMATION >
IGNITION SIGNAL
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
46
60
61
62L/R
GR/R
O/W
Y/RIgnition signal No. 7
Ignition signal No. 5
Ignition signal No. 3
Ignition signal No. 1[Engine is running]
•Warm-up condition
• Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle.0 - 0.2V
[Engine is running]
•Warm-up condition
• Engine speed: 2,000 rpm.0.1 - 0.4V
PBIB0044E
PBIB0045E

IGNITION SIGNAL
EC-631
< SERVICE INFORMATION >
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Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
BBWA1712E

EC-632
< SERVICE INFORMATION >
IGNITION SIGNAL
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnosis ProcedureINFOID:0000000003532179
1.CHECK ENGINE START
Turn ignition switch OFF, and restart engine.
Is engine running?
Ye s o r N o
Yes (With CONSULT-II)>>GO TO 2.
Yes (Without CONSULT-II)>>GO TO 3.
No >> GO TO 4.
2.CHECK OVERALL FUNCTION
With CONSULT-II
1. Perform “POWER BALANCE” in “ACTIVE TEST” mode with
CONSULT-II.
2. Make sure that each circuit produces a momentary engine
speed drop.
OK or NG
OK >>INSPECTION END
NG >> GO TO 10.
3.CHECK OVERALL FUNCTION
Without CONSULT-II
1. Let engine idle.
TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
65
79
80
81G/R
V/W
W/R
W/GIgnition signal No. 8
Ignition signal No. 6
Ignition signal No. 4
Ignition signal No. 2[Engine is running]
•Warm-up condition
• Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle.0 - 0.2V
[Engine is running]
•Warm-up condition
• Engine speed: 2,000 rpm.0.1 - 0.4V
PBIB0044E
PBIB0045E
PBIB0133E

IGNITION SIGNAL
EC-633
< SERVICE INFORMATION >
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2. Read the voltage signal between ECM terminals 46, 60, 61, 62,
65, 79, 80, 81 and ground with an oscilloscope.
3. Verify that the oscilloscope screen shows the signal wave as
shown below.
NOTE:
The pulse cycle changes depending on rpm at idle.
OK or NG
OK >>INSPECTION END
NG >> GO TO 10.
4.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
2. Check voltage between ECM terminals 119, 120 and ground
with CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> Go to EC-139
.
5.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect condenser-1 harness connector.
3. Turn ignition switch ON.
4. Check voltage between condenser-1 terminal 1 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III
1. Turn ignition switch OFF.
PBIB2094E
PBIB0044E
Voltage: Battery voltage
MBIB0034E
BBIA0358E
Voltage: Battery voltage
PBIB0624E

EC-634
< SERVICE INFORMATION >
IGNITION SIGNAL
2. Disconnect IPDM E/R connector E119.
3. Check harness continuity between IPDM E/R terminal 4 and condenser-1 terminal 1.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> Go to EC-139.
NG >> GO TO 7.
7.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E2, F32
• Harness for open or short between condenser-1 and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
8.CHECK CONDENSER-1 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between condenser-1 terminal 2 and ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to power in harness or connectors.
9.CHECK CONDENSER-1
Refer to EC-635, "
Component Inspection".
OK or NG
OK >> GO TO 10.
NG >> Replace condenser-1.
10.CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Disconnect ignition coil harness connector.
4. Turn ignition switch ON.Continuity should exist.
Continuity should exist.
1. Ignition coils (with power transistor)
(bank 2)2. Ignition coils (with power transistor)
(bank 1)
BBIA0777E

IGNITION SIGNAL
EC-635
< SERVICE INFORMATION >
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5. Check voltage between ignition coil terminal 3 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E2, F32
• Harness for open or short between ignition coil and harness connector F32
>> Repair or replace harness or connectors.
12.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 13.
NG >> Repair open circuit or short to power in harness or connectors.
13.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 14.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
14.CHECK IGNITION COIL WITH POWER TRANSISTOR
Refer to EC-635, "
Component Inspection".
OK or NG
OK >> GO TO 15.
NG >> Replace ignition coil with power transistor.
15.CHECK INTERMITTENT INCIDENT
Refer to EC-138
.
>>INSPECTION END
Component InspectionINFOID:0000000003532180
IGNITION COIL WITH POWER TRANSISTOR
CAUTION:Voltage: Battery voltage
PBIB0138E
Continuity should exist.
Continuity should exist.

EC-636
< SERVICE INFORMATION >
IGNITION SIGNAL
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.
CAUTION:
• Do not approach to the spark plug and the ignition coil
within 50cm. Be careful not to get an electrical shock
while checking, because the electrical discharge voltage
becomes 20kV or more.
• It might cause to damage the ignition coil if the gap of more than 17 mm is taken.
NOTE:
When the gap is less than 13 mm, the spark might be generated even if the coil is malfunctioning.
17. If NG, replace ignition coil with power transistor.
CONDENSER-1
1. Turn ignition switch OFF.
2. Disconnect condenser-1 harness connector.
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
BBIA0380E
PBIB2325E

IGNITION SIGNAL
EC-637
< SERVICE INFORMATION >
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3. Check resistance between condenser-1 terminals 1 and 2.
Removal and InstallationINFOID:0000000003532181
IGNITION COIL WITH POWER TRANSISTOR
Refer to EM-28.
Resistance Above 1 MΩ at 25°C (77°F)
PBIB0794E