2011 INFINITI QX56 ignition

P0335 CKP SENSOREC-301
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
>> INSPECTION END
7.CHECK CKP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between CKP sensor harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 8.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
8.CHECK CKP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check the continuity between CKP sensor harness connector and ECM harness connector.
2. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 9.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
9.CHECK CRANKSHAFT POSITION SENSOR
Refer to EC-301, "
Component Inspection (Crankshaft Position Sensor)".
Is the inspection result normal?
YES >> GO TO 10.
NO >> Replace crankshaft position sensor.
10.CHECK GEAR TOOTH
Visually check for chipping signal plate gear tooth.
Is the inspection result normal?
YES >> GO TO 11.
NO >> Replace the signal plate.
11 .CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (Cra nkshaft Position Sensor)INFOID:0000000006217847
1.CHECK CRANKSHAFT POSITION SENSOR-I
1. Turn ignition switch OFF.
2. Loosen the fixing bolt of the sensor.
3. Disconnect crankshaft positi on sensor harness connector.
4. Remove the sensor.
CKP sensor ECM Continuity
Connector Terminal Connector Terminal
F74 2 F110 98 Existed
CKP sensor ECM Continuity
Connector Terminal Connector Terminal
F74 3 F110 86 Existed
Revision: 2010 May2011 QX56

P0340, P0345 CMP SENSOREC-303
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0340, P0345 CMP SENSOR
DTC LogicINFOID:0000000006217848
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm th at battery voltage is 10.5 V or more with ignition
switch ON.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE-I
1. Start engine and let it idle for at least 5 seconds. If engine does not start, crank engine for at least 2 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-304, "Diagnosis Procedure".
NO >> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE-I
1. Maintain engine speed at more than 800 rpm for at least 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0340 CMP SEN/CIRC-B1
[Camshaft position sensor
(bank 1) 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
[Camshaft position sensor (bank 1) circuit is
open or shorted.]
(APP sensor 2 circuit is shorted.)
(Battery current sensor circuit is shorted.)
[Crankshaft position sensor circuit is shorted.]
(Refrigerant pressure sensor circuit is open or
shorted.)
(EVAP control system pressure sensor circuit
is open or shorted.)
 Camshaft position sensor (bank 1)
 Accelerator pedal position sensor
 Battery current sensor
 Crankshaft position sensor
 Refrigerant pressure sensor
 EVAP control system pressure sensor
 Camshaft (INT)
Starter motor
 Starting system circuit
 Dead (Weak) battery
P0345 CMP SEN/CIRC-B2
[Camshaft position sensor
(bank 2) circuit]  Harness or connectors
[Camshaft position sensor (bank 2) circuit is
open or shorted.]
 Camshaft position sensor (bank 2)
 Camshaft (INT)
Starter motor
 Starting system circuit
 Dead (Weak) battery
Revision: 2010 May2011 QX56

EC-304
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0340, P0345 CMP SENSOR
YES >> Go to
EC-304, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217849
1.CHECK STARTING SYSTEM
Turn ignition switch to START position.
Does the engine turn over? Does the starter motor operate?
YES >> GO TO 2.
NO >> Check starting system. (Refer to STR-11, "
Work Flow".)
2.CHECK CAMSHAFT POSITION SENSOR POWER SUPPLY CIRCUIT-I
1. Disconnect camshaft position (CMP) sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between CMP sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 8.
NO-1 >> P0340: GO TO 3.
NO-2 >> P0345: Repair open circuit, short to ground or short to power in harness or connectors.
3.CHECK CMP SENSOR POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between CMP sens or harness connector and ECM harness connector.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair open circuit.
4.CHECK SENSOR POWER SUPPLY CIRCUIT
Check harness for short to power and short to ground, between the following terminals.
Is the inspection result normal?
YES >> GO TO 5.
DTC CMP sensor
Ground Voltage (V)
Bank Connector Terminal
P0340 1 F84 1 Ground Approx. 5
P0345 2 F83 1
CMP sensor ECM Continuity
Bank Connector Terminal Connector Terminal
1 F84 1 F110 77 Existed
ECM Sensor
Connector Terminal Name Connector Terminal
F110 76 CKP sensor F74 1
77 Camshaft position sensor (bank 1) F84 1
E80 131
APP sensor 2 (Without ICC) E110 1
APP sensor 2 (With ICC) E67 9
133 Battery current sensor E63 2
Refrigerant pressure sensor E77 1
EVAP control system pressure sen-
sor
C17 3
Revision: 2010 May2011 QX56

P0340, P0345 CMP SENSOREC-305
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
NO >> Repair short to ground or short to power in harness or connectors.
5.CHECK COMPONENTS
Check the following.
 Battery current sensor (Refer to EC-414, "
Component Inspection (Battery Current Sensor)".)
 Crankshaft position sensor (Refer to EC-301, "
Component Inspection (Crankshaft Position Sensor)".)
 Refrigerant pressure sensor (Refer to EC-520, "
Component Function Check".)
 EVAP control system pressure sensor (Refer to EC-335, "
Component Inspection (EVAP Control System
Pressure Sensor)".)
Is the inspection result normal?
YES >> GO TO 6.
NO >> Replace malfunctioning component.
6.CHECK APP SENSOR
Refer to EC-470, "
Component Inspection (Accelerator Pedal Position Sensor)".
Is the inspection result normal?
YES >> GO TO 12.
NO >> GO TO 7.
7.REPLACE ACCELERATOR PEDAL ASSEMBLY
Replace accelerator pedal assembly. Refer to ACC-3, "
MODELS WITHOUT DISTANCE CONTROL ASSIST
SYSTEM : Removal and Installation" (Without distance control assist system) or ACC-4, "MODELS WITH
DISTANCE CONTROL ASSIST SYSTEM : Removal and Installation" (With distance control assist system).
>> INSPECTION END
8.CHECK CMP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between CMP sens or harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 9.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
9.CHECK CMP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check the continuity between CMP sens or harness connector and ECM harness connector.
2. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 10.
NO >> Repair open circuit, short to ground or short to power in harness or connectors.
10.CHECK CAMSHAFT POSITION SENSOR
Refer to EC-306, "
Component Inspection (Camshaft Position Sensor)".
Is the inspection result normal?
DTC CMP sensor ECM
Continuity
Bank Connector Terminal Connector Terminal
P0340 1 F84 2 F11068
Existed
P0345 2 F83 2 99
DTC CMP sensor ECM
Continuity
Bank Connector Terminal Connector Terminal
P0340 1 F84 3 F11095
Existed
P0345 2 F83 3 73
Revision: 2010 May2011 QX56

EC-306
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0340, P0345 CMP SENSOR
YES >> GO TO 11
NO >> Replace malfunctioning camshaft position sensor. Refer to
EM-61, "
Exploded View".
11 .CHECK CAMSHAFT (INT)
Check the following.
 Accumulation of debris to the signal plate of camshaft front end
 Chipping signal plate of camshaft front end
Is the inspection result normal?
YES >> GO TO 12.
NO >> Remove debris and clean the signal plate of camshaft
front end or replace camshaft.
12.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (Cam shaft Position Sensor)INFOID:0000000006217850
1.CHECK CAMSHAFT POSITION SENSOR-I
1. Turn ignition switch OFF.
2. Loosen the fixing bolt of the sensor.
3. Disconnect camshaft position sensor harness connector.
4. Remove the sensor.
5. Visually check the sensor for chipping.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace malfunctioning camshaft position sensor.
2.CHECK CAMSHAFT PO SITION SENSOR-II
Check resistance camshaft position sensor terminals as per the following.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace malfunctioning camshaft position sensor. Refer to EM-61, "
Exploded View".
JMBIA0962ZZ
JMBIA0065ZZ
Terminals (Polarity) Resistance
1 (+) - 2 (-) Except 0 or ∞ Ω [at 25 °C (77 °F)]
1 (+) - 3 (-)
2 (+) - 3 (-)
Revision: 2010 May2011 QX56

P0420, P0430 THREE WAY CATALYST FUNCTIONEC-307
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0420, P0430 THREE WAY CATALYST FUNCTION
DTC LogicINFOID:0000000006217851
DTC DETECTION LOGIC
The ECM monitors the switching frequency ratio of air fuel ratio (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 decr
eases, the heated oxygen sensor 2
switching frequency will increase.
When the frequency ratio of A/F sensor 1 and heated oxygen sensor
2 approaches a specified limit value, the three way catalyst (mani-
fold) malfunction is diagnosed.
DTC CONFIRMATION PROCEDURE
1.INSPECTION START
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 6.
2.PERFORM DTC CONFIRMATION PROCEDURE-I
WITH CONSULT-III
TESTING CONDITION:
Do not maintain engine speed for mo re than the specified minutes below.
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
6. Let engine idle for 1 minute.
7. Select “DATA MONITOR” mode with CONSULT-III.
8. Check 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).
9. Open engine hood.
10. Select “DTC & SRT CONFIRMATION” then “SRT WORK SUPPORT” mode with CONSULT-III.
11. Rev engine between 2,000 and 3,000 rpm and hold it for 3 consecutive minutes then release the acceler-
ator pedal completely.
12. Check the indication of “CATALYST”.
Which is displayed on CONSULT-III screen?
CMPLT >> GO TO 5.
INCMP >> GO TO 3.
PBIB2055E
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0420 TW CATALYST SYS-B1
[Catalyst system efficiency
below threshold (bank 1)]
 Three way catalyst (manifold) does not
operate properly.
 Three way catalyst (manifold) does not have enough oxygen storage capacity.  Three way catalyst (manifold)
 Exhaust tube
 Intake air leakage
 Fuel injector
 Fuel injector leakage
 Spark plug
 Improper ignition timing
P0430
TW CATALYST SYS-B2
[Catalyst system efficiency
below threshold (bank 2)]
Revision: 2010 May2011 QX56

EC-308
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0420, P0430 THREE
WAY CATALYST FUNCTION
3.PERFORM DTC CONFIRMATION PROCEDURE-II
1. Wait 5 seconds at idle.
2. Rev engine between 2,000 and 3,000 rpm and maintain it until “INCMP” of “CATALYST” changes to “CMPLT” (It will take approximately 5 minutes).
Does the indication change to
“CMPLT”?
YES >> GO TO 5.
NO >> GO TO 4.
4.PERFORM DTC CONFIRMATION PROCEDURE AGAIN
1. Stop engine and cool it down to less than 70 °C (158 °F).
2. Perform DTC CONFIRMATION PROCEDURE again.
>> GO TO 2.
5.PERFORM DTC CONFIRMATION PROCEDURE-III
Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-309, "Diagnosis Procedure".
NO >> INSPECTION END
6.PERFORM COMPONENT FUNCTION CHECK
WITH GST
Perform component function check. Refer to EC-308, "
Component Function Check".
NOTE:
Use component function check to check the overall functi on of the three way catalyst (manifold). During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-309, "
Diagnosis Procedure"
Component Function CheckINFOID:0000000006217852
1.PERFORM COMPONENT FUNCTION CHECK
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. Check the voltage between ECM harness connector terminals under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-309, "
Diagnosis Procedure".
DTC ECM
Condition Voltage
Connector +–
Terminal Terminal
P0420 F110 96
[HO2S2
(bank 1)] 100Keeping engine speed at 2,500 rpm
constant under no load The voltage fluctuation cycle takes more
than 5 seconds.
 1 cycle: 0.6 - 1.0
→ 0 - 0.3 → 0.6 - 1.0
P0430 87
[HO2S2
(bank 2)]
Revision: 2010 May2011 QX56

P0420, P0430 THREE WAY CATALYST FUNCTIONEC-309
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
Diagnosis ProcedureINFOID:0000000006217853
1.CHECK EXHAUST SYSTEM
Visually check exhaust tubes and muffler for dents.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace malfunctioning part.
2.CHECK EXHAUST GAS LEAKAGE
1. Start engine and run it at idle.
2. Listen for an exhaust gas leakage before the three way catalyst (manifold).
Is exhaust gas leakage detected?
YES >> Repair or replace malfunctioning part.
NO >> GO TO 3.
3.CHECK INTAKE AIR LEAKAGE
Listen for an intake air leakage after the mass air flow sensor.
Is intake air leakage detected?
YES >> Repair or replace malfunctioning part.
NO >> GO TO 4.
4.CHECK IDLE SPEED AND IGNITION TIMING
Check idle speed and ignition timing.
For procedure, refer to EC-530, "
Inspection" and EC-531, "Inspection".
For specification, refer to EC-538, "
Idle Speed" and EC-538, "Ignition Timing".
Is the inspection result normal?
YES >> GO TO 5.
NO >> Follow the EC-139, "
Work Procedure".
5.CHECK FUEL INJECTORS
Refer to EC-498, "
Component Function Check".
Is the inspection result normal?
YES >> GO TO 6.
NO >> Perform EC-498, "
Diagnosis Procedure".
6.CHECK FUNCTION OF IGNITION COIL-I
CAUTION:
Perform the following procedure in a place with no combustible objects and good ventilation.
1. Turn ignition switch OFF.
2. Remove fuel pump fuse in IPDM E/R to release fuel pressure.
NOTE:
 For the fuse number, refer to EC-114, "
Wiring Diagram".
 For the fuse arrangement, refer to PG-140, "
Fuse, Connector and Terminal Arrangement".
 Do not use CONSULT-III to release fuel pressure, or fuel pressure applies again during the following
procedure.
3. Start engine.
4. After engine stalls, crank it 2 or 3 times to release all fuel pressure.
5. Turn ignition switch OFF.
PBIB1216E
Revision: 2010 May2011 QX56