ignition INFINITI QX56 2009 Factory Service Manual
[x] Cancel search | Manufacturer: INFINITI, Model Year: 2009, Model line: QX56, Model: INFINITI QX56 2009Pages: 4171, PDF Size: 84.65 MB
Page 1518 of 4171
![INFINITI QX56 2009 Factory Service Manual
P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308 MISFIRE
EC-191
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
When disconnecting each fuel injector harness connector
INFINITI QX56 2009 Factory Service Manual
P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308 MISFIRE
EC-191
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
When disconnecting each fuel injector harness connector](/img/42/57031/w960_57031-1517.png)
P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308 MISFIRE
EC-191
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
When disconnecting each fuel injector harness connector
one at a time, is there any cylinder which does not
produce a momentary engine speed drop?
Ye s o r N o
Yes >> GO TO 4.
No >> GO TO 7.
4.CHECK FUEL INJECTOR
Does each fuel injector make an operating sound at idle?
Ye s o r N o
Yes >> GO TO 5.
No >> Check fuel injector(s) and circuit(s). Refer to EC-392,
"Diagnosis Procedure".
5.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:
BBIA0374E
PBIB1986E
Spark should be generated.
BBIA0380E
PBIB2325E
Revision: December 20092009 QX56
Page 1519 of 4171
![INFINITI QX56 2009 Factory Service Manual
EC-192
< COMPONENT DIAGNOSIS >[VK56DE]
P0300, P0301, P0302, P
0303, P0304, P0305, P0306, P0307, P0308 MISFIRE
Do not approach to the spark pl ug and the ignition coil within 50cm. Be careful not t INFINITI QX56 2009 Factory Service Manual
EC-192
< COMPONENT DIAGNOSIS >[VK56DE]
P0300, P0301, P0302, P
0303, P0304, P0305, P0306, P0307, P0308 MISFIRE
Do not approach to the spark pl ug and the ignition coil within 50cm. Be careful not t](/img/42/57031/w960_57031-1518.png)
EC-192
< COMPONENT DIAGNOSIS >[VK56DE]
P0300, P0301, P0302, P
0303, P0304, P0305, P0306, P0307, P0308 MISFIRE
Do not approach to the spark pl ug 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 9.
NG >> GO TO 6.
6.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 7.
NG >> Check ignition coil, power transistor and their circuits. Refer to EC-404, "Diagnosis Procedure"
.
7.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 8.
8.CHECK FUNCTION OF IGNITION COIL-III
1. Reconnect the initial spark plugs.
2. Crank engine for about 3 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".
9.CHECK COMPRESSION PRESSURE
Check compression pressure. Refer to EM-23, "Checking Compression Pressure"
.
OK or NG
OK >> GO TO 10.
NG >> Check pistons, piston rings, valves, valve seats and cylinder head gaskets.
10.CHECK FUEL PRESSURE
1. Install all removed parts.
2. Release fuel pressure to zero. Refer to EC-487, "Fuel Pressure Check"
.
3. Install fuel pressure gauge and check fuel pressure. Refer to EC-487, "Fuel Pressure Check"
.
Spark should be generated.
SEF156I
Spark should be generated.
At idling: Approximately 350 kPa (3.57 kg/cm
2 , 51 psi)
Revision: December 20092009 QX56
Page 1520 of 4171
![INFINITI QX56 2009 Factory Service Manual
P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308 MISFIRE
EC-193
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 .DETECT MALFU INFINITI QX56 2009 Factory Service Manual
P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308 MISFIRE
EC-193
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 .DETECT MALFU](/img/42/57031/w960_57031-1519.png)
P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308 MISFIRE
EC-193
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
Fuel pump and circuit (Refer to EC-395, "Diagnosis Procedure"
.)
Fuel pressure regulator (Refer to EC-487, "Fuel Pressure Check"
.)
Fuel lines
Fuel filter for clogging
>> Repair or replace.
12.CHECK IGNITION TIMING
Check the following items. Refer to EC-13, "Basic Inspection"
.
OK or NG
OK >> GO TO 13.
NG >> Follow the EC-13, "Basic Inspection"
.
13.CHECK A/F SENSOR 1 INPUT SIGNAL
1. Turn ignition switch OFF.
2. Disconnect A/F sensor 1 harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between the following terminals. Refer to Wiring Diagram.
5. Check harness continuity between the following terminals and ground. Refer to Wiring Diagram.
Items Specifications
Target idle speed 650 ± 50 rpm (in P or N position)
Ignition timing 15 ± 5 ° BTDC (in P or N position)
A/F sensor 1 terminal ECM terminal
Bank 1 135
256
Bank 2 116
275
Continuity should exist.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal 135116
256275
BBIA0376E
Revision: December 20092009 QX56
Page 1522 of 4171
![INFINITI QX56 2009 Factory Service Manual
P0327, P0328, P0332, P0333 KS
EC-195
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0327, P0328, P0332, P0333 KS
Component DescriptionINFOID:0000000003771457
The knock sensor is at INFINITI QX56 2009 Factory Service Manual
P0327, P0328, P0332, P0333 KS
EC-195
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0327, P0328, P0332, P0333 KS
Component DescriptionINFOID:0000000003771457
The knock sensor is at](/img/42/57031/w960_57031-1521.png)
P0327, P0328, P0332, P0333 KS
EC-195
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0327, P0328, P0332, P0333 KS
Component DescriptionINFOID:0000000003771457
The knock sensor is attached to t
he cylinder block. It senses engine
knocking using a piezoelectric el ement. A knocking vibration from
the cylinder block is sensed as vibrational pressure. This pressure is
converted into a voltage signal and sent to the ECM.
On Board Diagnosis LogicINFOID:0000000003771458
The MIL will not light up for these self-diagnoses.
DTC Confirmation ProcedureINFOID:0000000003771459
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
1. Start engine and run it for at least 5 seconds at idle speed.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-195, "Diagnosis Procedure"
Diagnosis ProcedureINFOID:0000000003771460
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 M Ω.
PBIB0021E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0327
0327
(bank 1) Knock sensor circuit low in-
put An excessively low voltage from the sensor
is sent to ECM.
Harness or connectors(The sensor circuit is open or shorted.)
Knock sensor
P0332
0332
(bank 2)
P0328
0328
(bank 1)
Knock sensor circuit high in-
put An excessively high voltage from the sensor
is sent to ECM.
P0333
0333
(bank 2)
Resistance: Approximately 532 - 588 k Ω [at 20 °C (68 °F)]
Revision: December 20092009 QX56
Page 1525 of 4171
![INFINITI QX56 2009 Factory Service Manual
EC-198
< COMPONENT DIAGNOSIS >[VK56DE]
P0335 CKP SENSOR (POS)
P0335 CKP SENSOR (POS)
Component DescriptionINFOID:0000000003771462
The crankshaft position sensor (P
OS) is located on the A/T assem-
bl INFINITI QX56 2009 Factory Service Manual
EC-198
< COMPONENT DIAGNOSIS >[VK56DE]
P0335 CKP SENSOR (POS)
P0335 CKP SENSOR (POS)
Component DescriptionINFOID:0000000003771462
The crankshaft position sensor (P
OS) is located on the A/T assem-
bl](/img/42/57031/w960_57031-1524.png)
EC-198
< COMPONENT DIAGNOSIS >[VK56DE]
P0335 CKP SENSOR (POS)
P0335 CKP SENSOR (POS)
Component DescriptionINFOID:0000000003771462
The crankshaft position sensor (P
OS) is located on the A/T assem-
bly facing the gear teeth (cogs) of the signal plate. It detects the fluc-
tuation of the engine revolution.
The sensor consists of a permanent magnet and Hall IC.
When the 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.
The ECM receives the voltage signal and detects the fluctuation of
the engine revolution.
ECM receives the signals as shown in the figure.
On Board Diagn osis LogicINFOID:0000000003771463
DTC Confirmation ProcedureINFOID:0000000003771464
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following pro cedure, confirm that battery voltage is more than 10.5V with igni-
tion switch ON.
1. Crank engine for at least 2 seconds and run it for at least 5 seconds at idle speed.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-199, "Diagnosis Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-III” above.
PBIB0562E
PBIB3459E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0335
0335 Crankshaft position sen-
sor (POS) circuit The crankshaft position sensor (POS) signal
is not detected by the ECM during the first
few seconds of engine cranking.
The proper pulse signal from the crankshaft position sensor (POS) is not sent to ECM
while the engine is running.
The crankshaft position sensor (POS) signal is not in the normal pattern during engine run-
ning. Harness or connectors
(The sensor circuit is open or shorted)
Crankshaft position sensor (POS)
Signal plate
Revision: December 20092009 QX56
Page 1526 of 4171
![INFINITI QX56 2009 Factory Service Manual
P0335 CKP SENSOR (POS)EC-199
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
Diagnosis ProcedureINFOID:0000000003771465
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loo INFINITI QX56 2009 Factory Service Manual
P0335 CKP SENSOR (POS)EC-199
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
Diagnosis ProcedureINFOID:0000000003771465
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loo](/img/42/57031/w960_57031-1525.png)
P0335 CKP SENSOR (POS)EC-199
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
Diagnosis ProcedureINFOID:0000000003771465
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-85, "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
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 crank shaft 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 C KP sensor (POS) terminal 1 and ground.
Refer to Wiring Diagram.
BBIA0354E
BBIA0367E
Voltage: Battery voltage
SEF481Y
Revision: December 20092009 QX56
Page 1529 of 4171
![INFINITI QX56 2009 Factory Service Manual
EC-202
< COMPONENT DIAGNOSIS >[VK56DE]
P0340 CMP SENSOR (PHASE)
P0340 CMP SENSOR (PHASE)
Component DescriptionINFOID:0000000003771467
The camshaft position sensor (P
HASE) senses the protrusion of
ex INFINITI QX56 2009 Factory Service Manual
EC-202
< COMPONENT DIAGNOSIS >[VK56DE]
P0340 CMP SENSOR (PHASE)
P0340 CMP SENSOR (PHASE)
Component DescriptionINFOID:0000000003771467
The camshaft position sensor (P
HASE) senses the protrusion of
ex](/img/42/57031/w960_57031-1528.png)
EC-202
< COMPONENT DIAGNOSIS >[VK56DE]
P0340 CMP SENSOR (PHASE)
P0340 CMP SENSOR (PHASE)
Component DescriptionINFOID:0000000003771467
The camshaft position sensor (P
HASE) 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, utilizi ng 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 Diagn osis LogicINFOID:0000000003771468
DTC Confirmation ProcedureINFOID:0000000003771469
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following pro cedure, confirm that battery voltage is more than 10.5V with igni-
tion switch ON.
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-203, "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-203, "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-18
.)
Starting system circuit (Refer to STR-18
.)
Dead (Weak) battery
Revision: December 20092009 QX56
Page 1530 of 4171
![INFINITI QX56 2009 Factory Service Manual
P0340 CMP SENSOR (PHASE)EC-203
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
Diagnosis ProcedureINFOID:0000000003771470
1.CHECK STARTING SYSTEM
Turn ignition switch to START positi INFINITI QX56 2009 Factory Service Manual
P0340 CMP SENSOR (PHASE)EC-203
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
Diagnosis ProcedureINFOID:0000000003771470
1.CHECK STARTING SYSTEM
Turn ignition switch to START positi](/img/42/57031/w960_57031-1529.png)
P0340 CMP SENSOR (PHASE)EC-203
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
Diagnosis ProcedureINFOID:0000000003771470
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 STR-18
.)
2.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-85, "Ground Inspection"
.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace ground connections.
3.CHECK CAMSHAFT POSITION (CMP) SEN SOR (PHASE) POWER SUPPLY CIRCUIT
1. Disconnect camshaft position (C MP) 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.
4.DETECT MALFUNCTIONING PART
Check the following.
Harness connectors F32, E2 Does the engine turn over?
Does the starter motor operate?
BBIA0354E
BBIA0740E
Voltage: Battery voltage
SEF481Y
Revision: December 20092009 QX56
Page 1531 of 4171
![INFINITI QX56 2009 Factory Service Manual
EC-204
< COMPONENT DIAGNOSIS >[VK56DE]
P0340 CMP SENSOR (PHASE)
Harness for open or short between cams
haft position sensor (PHASE) and ECM
Harness for open or short between camshaft position se INFINITI QX56 2009 Factory Service Manual
EC-204
< COMPONENT DIAGNOSIS >[VK56DE]
P0340 CMP SENSOR (PHASE)
Harness for open or short between cams
haft position sensor (PHASE) and ECM
Harness for open or short between camshaft position se](/img/42/57031/w960_57031-1530.png)
EC-204
< COMPONENT DIAGNOSIS >[VK56DE]
P0340 CMP SENSOR (PHASE)
Harness for open or short between cams
haft 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 between 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 terminal 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 POSITION SENSOR (PHASE)
Refer to EC-204, "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:0000000003771471
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: December 20092009 QX56
Page 1533 of 4171
![INFINITI QX56 2009 Factory Service Manual
EC-206
< COMPONENT DIAGNOSIS >[VK56DE]
P0420, P0430 THREE
WAY CATALYST FUNCTION
P0420, P0430 THREE WAY CATALYST FUNCTION
On Board Diagnosis LogicINFOID:0000000003771472
The ECM monitors the switchin INFINITI QX56 2009 Factory Service Manual
EC-206
< COMPONENT DIAGNOSIS >[VK56DE]
P0420, P0430 THREE
WAY CATALYST FUNCTION
P0420, P0430 THREE WAY CATALYST FUNCTION
On Board Diagnosis LogicINFOID:0000000003771472
The ECM monitors the switchin](/img/42/57031/w960_57031-1532.png)
EC-206
< COMPONENT DIAGNOSIS >[VK56DE]
P0420, P0430 THREE
WAY CATALYST FUNCTION
P0420, P0430 THREE WAY CATALYST FUNCTION
On Board Diagnosis LogicINFOID:0000000003771472
The ECM monitors the switching frequency ratio of air fuel sensor
(A/F) sensor 1 and heat ed 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 decr eases, 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 specif ied limit value, the three way
catalyst (manifold) malfunction is diagnosed.
DTC Confirmation ProcedureINFOID:0000000003771473
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
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 “C OOLAN TEMP/S” indication reaches to 70°C (158 °F).
7. Open engine hood.
8. Select “DTC & SRT CONFIRMATION” then “S RT 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 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-III.
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: December 20092009 QX56