2008 INFINITI QX56 ignition

EC-208
< COMPONENT DIAGNOSIS >[VK56DE]
P0335 CKP SENSOR (POS)
Diagnosis Procedure
INFOID:0000000001351558
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-86, "
Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK CRANKSHAFT POSITION (CKP) SE NSOR (POS) POWER SUPPLY CIRCUIT
1. Disconnect crankshaft position (CKP) sensor (POS) harness connector.
2. Turn ignition switch ON.
3. Check voltage between CKP sensor (POS) terminal 3 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors F32, E2
• Harness for open or short between cran kshaft position sensor (POS) and ECM
• Harness for open or short between crankshaf t position sensor (POS) and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK CKP SENSOR (POS) GRO UND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between CK P sensor (POS) terminal 1 and ground.
Refer to Wiring Diagram.
BBIA0354E
BBIA0367E
Voltage: Battery voltage
SEF481Y
Revision: March 2010 2008 QX56

P0340 CMP SENSOR (PHASE)EC-211
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0340 CMP SENSOR (PHASE)
Component DescriptionINFOID:0000000001351561
The camshaft position sensor (PHASE) senses the protrusion of
exhaust valve cam sprocket to identify a particular cylinder. The
camshaft position sensor (PHASE) senses the piston position.
When the crankshaft position sensor (POS) system becomes inoper-
ative, the camshaft position sensor
(PHASE) provides various con-
trols of engine parts instead, utilizing timing of cylinder identification
signals.
The sensor consists of a permanent magnet and Hall IC.
When engine is running, the high and low parts of the teeth cause
the gap with the sensor to change.
The changing gap causes the magnetic field near the sensor to
change.
Due to the changing magnetic field, the voltage from the sensor changes.
ECM receives the signals as shown in the figure.
On Board Diagnosis LogicINFOID:0000000001351562
DTC Confirmation ProcedureINFOID:0000000001351563
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm th at battery voltage is more than 10.5V with igni-
tion switch ON.
WITH CONSULT-III
1. Turn ignition switch ON.
2. Crank engine for at least 2 seconds and run it for at least 5 seconds at idle speed.
3. Check 1st trip DTC.
4. If 1st trip DTC is detected, go to EC-212, "
Diagnosis Procedure".
If 1st trip DTC is not detected, go to next step.
5. Maintaining engine speed at more than 800 rpm for at least 5 seconds.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to EC-212, "
Diagnosis Procedure".
PBIB0562E
PBIB3459E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0340
0340 Camshaft position sen-
sor (PHASE) circuit • The cylinder No. signal is not sent to ECM for
the first few seconds during engine cranking.
• The cylinder No. signal is not sent to ECM during engine running.
• The cylinder No. signal is not in the normal
pattern during engine running. • Harness or connectors
(The sensor circuit is open or shorted)
• Camshaft position sensor (PHASE)
• Camshaft (Exhaust)
• Starter motor (Refer to STR-17
.)
• Starting system ci rcuit (Refer to STR-17
.)
• Dead (Weak) battery
Revision: March 2010 2008 QX56

EC-212
< COMPONENT DIAGNOSIS >[VK56DE]
P0340 CMP SENSOR (PHASE)
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351565
1.CHECK STARTING SYSTEM
Turn ignition switch to START position.
Ye s o r N o
Ye s > > G O T O 2 .
No >> Check starting system. (Refer to STR-17
.)
2.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-86, "
Ground Inspection".
OK or NG
OK >> GO TO 3.
NG >> Repair or replace ground connections.
3.CHECK CAMSHAFT POSITION (CMP) SENS OR (PHASE) POWER SUPPLY CIRCUIT
1. Disconnect camshaft position (CMP) sensor (PHASE) (2) har- ness connector.
- Radiator hose (1)
2. Turn ignition switch ON.
3. Check voltage between CMP sensor (PHASE) terminal 3 and
ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
Does the engine turn over?
Does the starter motor operate?
BBIA0354E
BBIA0740E
Voltage: Battery voltage
SEF481Y
Revision: March 2010 2008 QX56

P0340 CMP SENSOR (PHASE)EC-213
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
4.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors F32, E2
• Harness for open or short between camshaft position sensor (PHASE) and ECM
• Harness for open or short between camshaft position sensor (PHASE) and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK CMP SENSOR (PHASE) GRO UND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between CMP sensor (PHASE) terminal 1 and ground. Refer to wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors F32, E2
• Harness for open or short betw een CMP sensor (PHASE) and ground
>> Repair open circuit or short to power in harness or connectors.
7.CHECK CMP SENSOR (PHASE) INPUT SI GNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM termi nal 14 and CMP sensor (PHASE) terminal 2.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8.CHECK CAMSHAFT POSITI ON SENSOR (PHASE)
Refer to EC-213, "
Component Inspection".
OK or NG
OK >> GO TO 9.
NG >> Replace camshaft position sensor (PHASE).
9.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000001351566
CAMSHAFT POSITION SENSOR (PHASE)
1. Loosen the fixing bolt of the sensor.
2. Disconnect camshaft position s ensor (PHASE) harness connector.
3. Remove the sensor. Continuity should exist.
Continuity should exist.
Revision: March 2010
2008 QX56

P0420, P0430 THREE WAY CATALYST FUNCTIONEC-215
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0420, P0430 THREE WAY CATALYST FUNCTION
On Board Diagnosis LogicINFOID:0000000001351568
The ECM monitors the switching
frequency ratio of air fuel sensor
(A/F) sensor 1 and heated oxygen sensor 2.
A three way catalyst (manifold) with high oxygen storage capacity
will indicate a low switching frequency of heated oxygen sensor 2.
As oxygen storage capacity decreases, the heated oxygen sensor 2
switching frequency will increase.
When the frequency ratio of air fuel ratio (A/F) sensor 1 and heated
oxygen sensor 2 approaches a specified limit value, the three way
catalyst (manifold) malfunction is diagnosed.
DTC Confirmation ProcedureINFOID:0000000001351569
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-III
TESTING CONDITION:
Do not hold engine speed for more than the specified minutes below.
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
2. Start engine and warm it up to the normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S” indicates more than 70 °C (158° F).
If not, warm up engine and go to next step when “COOLAN TEMP/S” indication reaches to 70°C (158° F).
7. Open engine hood.
8. Select “DTC & SRT CONFIRMATION” then “SRT WORK SUPPORT” mode with CONSULT-III.
9. Rev engine up to 2,000 to 3,000 rpm and hold it for 3 consecutive 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 unt il “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 RESU LTS” mode with CONSULT-III.
13. Confirm that the 1st trip DTC is not detected. If the 1st trip DTC is detected, go to EC-216, "
Diagnosis Procedure".
PBIB2055E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0420
0420
(Bank 1) Catalyst system efficien-
cy below threshold • Three way catalyst (manifold) does not oper-
ate properly.
• Three way catalyst (manifold) does not have enough oxygen storage capacity. • Three way catalyst (manifold)
• Exhaust tube
• Intake air leaks
• Fuel injector
• Fuel injector leaks
• Spark plug
• Improper ignition timing
P0430
0430
(Bank 2)
Revision: March 2010
2008 QX56

EC-216
< COMPONENT DIAGNOSIS >[VK56DE]
P0420, P0430 THREE WAY CATALYST FUNCTION
Overall Function Check
INFOID:0000000001351570
Use this procedure to check the overall function of the th ree 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-216, "
Diagnosis Procedure".
• 1 cycle: 0.6 - 1.0 → 0 - 0.3 → 0.6 - 1.0
Diagnosis ProcedureINFOID:0000000001351571
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-13, "
Basic Inspection".
PBIB2056E
PBIB1216E
Revision: March 2010 2008 QX56

P0420, P0430 THREE WAY CATALYST FUNCTIONEC-217
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
OK or NG
OK >> GO TO 5.
NG >> Follow the
EC-13, "
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-III or tester.
Refer to Wiring Diagram for fuel injector, EC-439, "
Wiring Dia-
gram - ENGINE CONTROL SYSTEM -".
OK or NG
OK >> GO TO 6.
NG >> Perform EC-411, "
Diagnosis Procedure".
6.CHECK FUNCTION OF IGNITION COIL-I
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-III 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 coilwithin 50cm. Be careful not to get an electrical shock
while checking, because the el ectrical 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.
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
Spark should be generated.
BBIA0380E
PBIB2325E
Revision: March 2010 2008 QX56

EC-218
< COMPONENT DIAGNOSIS >[VK56DE]
P0420, P0430 THREE WAY CATALYST FUNCTION
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-411, "
Diagnosis Procedure".
8.CHECK SPARK PLUG
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-16, "
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-
16, "Removal and Installation".
10.CHECK FUEL INJECTOR
1. Turn ignition switch OFF.
2. Remove fuel injector assembly. Refer to EM-40, "
Removal and Installation".
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 GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
Trouble is fixed.>> INSPECTION END
Trouble is not fixed.>>Replace three way catalyst assembly. Spark should be generated.
SEF156I
Spark should be generated.
Revision: March 2010
2008 QX56