check engine INFINITI QX56 2007 Factory Service Manual

EC-334
< SERVICE INFORMATION >
DTC P0327, P0328, P0332, P0333 KS
Diagnosis Procedure
INFOID:0000000003531829
1.CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-I
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check resistance between ECM terminals 15, 36 and ground. Refer to Wiring Diagram.
NOTE:
It is necessary to use an ohmmeter which can measure more than 10 MΩ.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2.CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-II
1. Disconnect knock sensor harness connector.
2. Check harness continuity between ECM terminal 15 and knock
sensor (bank1) terminal 1, ECM terminal 36 and knock sensor
(bank 2) terminal 1.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors F26, F101
• Harness for open or short between ECM and knock sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK KNOCK SENSOR
Refer to EC-335, "
Component Inspection".
OK or NG
OK >> GO TO 5.
NG >> Replace malfunctioning knock sensor.
5.CHECK GROUND CONNECTIONS
Loosen and retighten three ground screws on the body.
TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
15
36W
WKnock sensor (bank 1)
Knock sensor (bank 2)[Engine is running]
• Idle speedApproximately 2.5V
Resistance: Approximately 532 - 588 kΩ [at 20°C (68°F)]
Continuity should exist.
PBIB0021E

DTC P0335 CKP SENSOR (POS)
EC-339
< SERVICE INFORMATION >
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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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnosis ProcedureINFOID:0000000003531837
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-143, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK CRANKSHAFT POSITION (CKP) SENSOR (POS) POWER SUPPLY CIRCUIT
TER-
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NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
13 OCrankshaft position sensor
(POS)[Engine is running]
•Warm-up condition
• Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle. 1.0 - 2.0V
[Engine is running]
• Engine speed: 2,000 rpm.1.0 - 2.0V
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 ignition
switch OFFBATTERY VOLTAGE
(11 - 14V)
11 9
120BR
BRPower supply for ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
PBIB1041E
PBIB1042E
BBIA0354E

DTC P0340 CMP SENSOR (PHASE)
EC-345
< SERVICE INFORMATION >
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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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnosis ProcedureINFOID:0000000003531844
1.CHECK STARTING SYSTEM
Turn ignition switch to START position.
Ye s o r N o
Yes >> GO TO 2.
No >> Check starting system. (Refer to SC-9
.)
2.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
TER-
MI-
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NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
14 YCamshaft position sensor
(PHASE)[Engine is running]
•Warm-up condition
• Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle.1.0 - 4.0V
[Engine is running]
• Engine speed: 2,000 rpm.1.0 - 4.0V
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)
PBIB1039E
PBIB1040E
Does the engine turn over?
Does the starter motor operate?

EC-348
< SERVICE INFORMATION >
DTC P0340 CMP SENSOR (PHASE)
5. Check resistance as shown in the figure.
Removal and InstallationINFOID:0000000003531846
CAMSHAFT POSITION SENSOR (PHASE)
Removal
1. Remove engine room cover using power tool. Refer to EM-12, "Removal and Installation".
2. Remove air duct and resonator assembly. Refer to EM-15, "
Removal and Installation".
3. Disconnect camshaft position sensor connector.
4. Remove camshaft position sensor (2) from intake valve timing
control solenoid valve cover (LH) (1).
Installation
Installation is in the reverse order of removal.
CAUTION:
Replace the O-ring (3) of the camshaft position sensor with a new one, then lubricate o-ring with
engine oil before installing.
Terminal No. (Polarity) Resistance Ω [at 25°C (77°F)]
3(+) - 1 (-)
Except 0 or ∞ 2 (+) - 1 (-)
3 (+) - 2 (-)
PBIB0564E
LBIA0479E
Camshaft position sensor : 9.6 N·m (0.98 kg-m, 5 in-bl)

EC-350
< SERVICE INFORMATION >
DTC P0420, P0430 THREE WAY CATALYST FUNCTION
8. Select “DTC & SRT CONFIRMATION” then “SRT WORK SUP-
PORT” mode with CONSULT-II.
9. Rev engine up to 2,000 to 3,000 rpm and hold it for 3 consecu-
tive minutes then release the accelerator pedal completely.
If “INCMP” of “CATALYST” changed to “CMPLT”, go to step 12.
10. Wait 5 seconds at idle.
11. Rev engine up to 2,000 to 3,000 rpm and maintain it until
“INCMP” of “CATALYST” changes to “CMPLT” (It will take
approximately 5 minutes).
If not “CMPLT”, stop engine and cool it down to less than 70°C
(158°F) and then retest from step 1.
12. Select “SELF-DIAG RESULTS” mode with CONSULT-II.
13. Confirm that the 1st trip DTC is not detected.
If the 1st trip DTC is detected, go to EC-351, "
Diagnosis Proce-
dure".
Overall Function CheckINFOID:0000000003531849
Use this procedure to check the overall function of the three way catalyst (manifold). During this check, a 1st
trip DTC might not be confirmed.
WITH GST
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Open engine hood.
6. Set voltmeter probes between ECM terminals ECM terminals 55
[HO2S2 (bank 1) signal], 74 [HO2S2 (bank 2) signal] and
ground.
7. Keep engine speed at 2,500 rpm constant under no load.
8. Make sure that the voltage does not vary for more than 5 sec-
onds.
If the voltage fluctuation cycle takes less than 5 seconds, go to
EC-351, "
Diagnosis Procedure".
• 1 cycle: 0.6 - 1.0 → 0 - 0.3 → 0.6 - 1.0
PBIB1784E
PBIB1785E
SEF535Z
PBIB2056E

DTC P0420, P0430 THREE WAY CATALYST FUNCTION
EC-351
< SERVICE INFORMATION >
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Diagnosis ProcedureINFOID:0000000003531850
1.CHECK EXHAUST SYSTEM
Visually check exhaust tubes and muffler for dent.
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2.CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before the three way catalyst (manifold).
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
3.CHECK INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
4.CHECK IGNITION TIMING
Check the following items. Refer to EC-71, "
Basic Inspection".
OK or NG
OK >> GO TO 5.
NG >> Follow the EC-71, "
Basic Inspection".
5.CHECK FUEL INJECTOR
1. Stop engine and then turn ignition switch ON.
2. Check voltage between ECM terminals 21, 22, 23, 40, 41, 42,
44, 63 and ground with CONSULT-II or tester.
Refer to Wiring Diagram for fuel injector, EC-609, "
Wiring Dia-
gram".
OK or NG
OK >> GO TO 6.
NG >> Perform EC-610, "
Diagnosis Procedure".
6.CHECK FUNCTION OF IGNITION COIL-I
PBIB1216E
Items Specifications
Target idle speed 650 ± 50 rpm (in P or N position)
Ignition timing 15 ± 5° BTDC (in P or N position)
Battery voltage should exist.
PBIB1527E

EC-352
< SERVICE INFORMATION >
DTC P0420, P0430 THREE WAY CATALYST FUNCTION
CAUTION:
Do the following procedure in the place where ventilation is good without the combustible.
1. Turn ignition switch OFF.
2. Remove fuel pump fuse in IPDM E/R to release fuel pressure.
NOTE:
Do not use CONSULT-II to release fuel pressure, or fuel pres-
sure applies again during the following procedure.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel
pressure.
5. Turn ignition switch OFF.
6. Remove all ignition coil harness connectors to avoid the electri-
cal discharge from the ignition coils.
7. Remove ignition coil and spark plug of the cylinder to be
checked.
8. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
9. Connect spark plug and harness connector to ignition coil.
10. 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.
11. 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.
OK or NG
OK >> GO TO 10.
NG >> GO TO 7.
7.CHECK FUNCTION OF IGNITION COIL-II
1. Turn ignition switch OFF.
2. Disconnect spark plug and connect a known-good spark plug.
3. Crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and
the grounded metal portion.
OK or NG
OK >> GO TO 8.
NG >> Check ignition coil, power transistor and their circuits. Refer to EC-626
.
8.CHECK SPARK PLUGSpark should be generated.
BBIA0380E
PBIB2325E
Spark should be generated.

DTC P0420, P0430 THREE WAY CATALYST FUNCTION
EC-353
< SERVICE INFORMATION >
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Check the initial spark plug for fouling, etc.
OK or NG
OK >> Replace malfunctioning spark plug(s) with standard type
one(s). For spark plug type, refer to EM-29, "
Removal
and Installation".
NG >> 1. Repair or clean spark plug.
2. GO TO 9.
9.CHECK FUNCTION OF IGNITION COIL-III
1. Reconnect the initial spark plugs.
2. Crank engine for about three seconds, and recheck whether spark is generated between the spark plug
and the grounded portion.
OK or NG
OK >>INSPECTION END
NG >> Replace malfunctioning spark plug(s) with standard type one(s). For spark plug type, refer to EM-
29, "Removal and Installation".
10.CHECK FUEL INJECTOR
1. Turn ignition switch OFF.
2. Remove fuel injector assembly.
Refer to EM-31
.
Keep fuel hose and all fuel injectors connected to fuel injector gallery.
3. Disconnect all ignition coil harness connectors.
4. Reconnect all fuel injector harness connectors disconnected.
5. Turn ignition switch ON.
Make sure fuel does not drip from fuel injector.
OK or NG
OK (Does not drip.)>>GO TO 11.
NG (Drips.)>>Replace the fuel injector(s) from which fuel is dripping.
11 .CHECK INTERMITTENT INCIDENT
Refer to EC-138
.
Trouble is fixed.>>INSPECTION END
Trouble is not fixed.>>Replace three way catalyst assembly.
SEF156I
Spark should be generated.

DTC P0441 EVAP CONTROL SYSTEM
EC-355
< SERVICE INFORMATION >
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2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and let it idle for at least 70 seconds.
4. Select “PURG FLOW P0441” of “EVAPORATIVE SYSTEM” in “DTC CONFIRMATION” mode with CON-
SULT-II.
5. Touch “START”.
If “COMPLETED” is displayed, go to step 7.
6. When the following conditions are met, “TESTING” will be displayed on the CONSULT-II screen. Maintain
the conditions continuously until “TESTING” changes to “COMPLETED”. (It will take at least 35 seconds.)
If “TESTING” is not changed for a long time, retry from step 2.
7. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”. If “NG” is displayed, refer to EC-
356, "Diagnosis Procedure".
Overall Function CheckINFOID:0000000003531854
Use this procedure to check the overall monitoring function of the EVAP control system purge flow monitoring.
During this check, a 1st trip DTC might not be confirmed.
WITH GST
1. Lift up drive wheels.
2. Start engine (VDC switch OFF) and warm it up to normal operating temperature.
3. Turn ignition switch OFF, wait at least 10 seconds.
4. Start engine and wait at least 70 seconds.
5. Set voltmeter probes to ECM terminals 32 (EVAP control system
pressure sensor signal) and ground.
6. Check EVAP control system pressure sensor value at idle speed
and note it.
7. Establish and maintain the following conditions for at least 1
minute.
8. Verify that EVAP control system pressure sensor value stays 0.1V less than the value at idle speed (mea-
sured at step 6) for at least 1 second.
9. If NG, go to EC-356, "
Diagnosis Procedure".
Selector lever Suitable position
VHCL SPEED SE 32 - 120 km/h (20 - 75 MPH)
ENG SPEED 500 - 3,000 rpm
B/FUEL SCHDL 1.0 - 12.0 msec
COOLAN TEMP/S 0 - 119°C (32 - 246°F)
PBIB0826E
Air conditioner switch ON
Headlamp switch ON
Rear window defogger switch ON
Engine speed Approx. 3,000 rpm
Gear position Any position other than P, N or R
PBIB1109E

EC-356
< SERVICE INFORMATION >
DTC P0441 EVAP CONTROL SYSTEM
Diagnosis Procedure
INFOID:0000000003531855
1.CHECK EVAP CANISTER
1. Turn ignition switch OFF.
2. Check EVAP canister for cracks.
OK or NG
OK (With CONSULT-II)>>GO TO 2.
OK (Without CONSULT-II)>>GO TO 3.
NG >> Replace EVAP canister.
2.CHECK PURGE FLOW
With CONSULT-II
1. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP ser-
vice port and install vacuum gauge. For the location of EVAP service port, refer to EC-33, "
Description".
2. Start engine and let it idle.
3. Select “PURG VOL CONT/V” in “ACTIVE TEST” mode with CONSULT-II.
4. Rev engine up to 2,000 rpm.
5. Touch “Qd” and “Qu” on CONSULT-II screen to adjust “PURG
VOL CONT/V” opening and check vacuum existence.
OK or NG
OK >> GO TO 7.
NG >> GO TO 4.
3.CHECK PURGE FLOW
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Stop engine.
3. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP ser-
vice port and install vacuum gauge. For the location of EVAP service port, refer to EC-33, "
Description".
4. Start engine and let it idle.
Do not depress accelerator pedal even slightly.
5. Check vacuum gauge indication before 60 seconds passed after starting engine.
6. Revving engine up to 2,000 rpm after 100 seconds passed after starting engine.
OK or NG
OK >> GO TO 7.
NG >> GO TO 4.
4.CHECK EVAP PURGE LINE
1. Turn ignition switch OFF.
2. Check EVAP purge line for improper connection or disconnection.
Refer to EC-33, "
Description".
OK or NG
OK >> GO TO 5.
NG >> Repair it.
5.CHECK EVAP PURGE HOSE AND PURGE PORT
PURG VOL CONT/V Vacuum
100% Should exist.
0% Should not exist.
PBIB1678E
Vacuum should not exist.
Vacuum should exist.