2011 INFINITI QX56 BATTERY

EC-374
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0603 ECM POWER SUPPLY
P0603 ECM POWER SUPPLY
DTC LogicINFOID:0000000006217873
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON wait at least 10 seconds.
2. Turn ignition switch OFF and wait at least 5 minutes.
3. Turn ignition switch ON, wait at least 10 seconds.
4. Repeat step 2 and 3 for five times.
5. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-374, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217874
1.CHECK ECM POWER SUPPLY
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the voltage between ECM harness connector terminals.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
 20 A fuse (No. 43)
 Harness for open or short between ECM and battery
 Loose or poor connection for each connector and harness
>> Repair or replace harness or connectors.
3.CHECK INTERMITTENT INCIDENT
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0603 ECM BACK UP/CIRCUIT
(ECM power supply circuit) ECM back up RAM system does not
function properly.  Harness or connectors
[ECM power supply (back up) circuit is open or
shorted.]
ECM
ECM
Vol tag e
+–
Connector Terminal Connector Terminal E80 156 E80 175 Battery voltage
Revision: 2010 May2011 QX56

EC-376
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0605 ECM
P0605 ECM
DTC LogicINFOID:0000000006217875
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 that battery voltage is 11 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROC EDURE FOR MALFUNCTION A AND D
1. Turn ignition switch ON.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-376, "Diagnosis Procedure".
NO >> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B
1. Turn ignition switch ON and wait at least 1 second.
2. Turn ignition switch OFF, wait at least 10 seconds, and then turn it ON.
3. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-376, "Diagnosis Procedure".
NO >> GO TO 4.
4.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION C
1. Turn ignition switch ON and wait at least 1 second.
2. Turn ignition switch OFF, wait at least 10 seconds, and then turn it ON.
3. Repeat step 2 for 32 times.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-376, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217876
1.INSPECTION START
1. Turn ignition switch ON.
2. Erase DTC.
3. Perform DTC Confirmation Procedure. See EC-376, "
DTC Logic".
Is the 1st trip DTC P0605 displayed again?
YES >> GO TO 2.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0605 Engine control module A) ECM calculation function is malfunctioning.
ECM
B) ECM EEP-ROM system is malfunctioning.
C) ECM self shut-off function is malfunctioning.
D) ECM temperature sensor is malfunctioning.
Revision: 2010 May2011 QX56

EC-380
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P062B ECM
P062B ECM
DescriptionINFOID:0000000006217879
This DTC is detected when the ECM-integrated injector dr
iver unit has a malfunction. For injector driver unit,
refer to EC-23, "
ECM".
DTC LogicINFOID:0000000006217880
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 that battery voltage is 11 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start the engine and keep the engine speed at idle for 30 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-380, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217881
1.CHECK FUEL INJECTOR
Perform fuel injector. Refer to EC-498, "
Component Function Check".
Is inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace error-detected parts.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Erase DTC.
3. Perform DTC cfirmation procedure again. Refer to EC-380, "
DTC Logic".
4. Check 1st trip DTC.
Is the DTC P062B displayed again?
YES >> Replace ECM. Refer to EC-535, "Removal and Installation".
NO >> INSPECTION END
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P062B Internal control module fuel injector
control performance Injector driver unit is malfunctioning.  Harness and connectors
(Injector circuit is open or
shorted)
 Battery power supply
 ECM (injector driver unit)
Revision: 2010 May2011 QX56

P0643 SENSOR POWER SUPPLYEC-381
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0643 SENSOR POWER SUPPLY
DTC LogicINFOID:0000000006217882
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, confi rm that battery voltage is 8 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for 1 second.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-381, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217883
1.CHECK ACCELERATOR PEDAL POSITION SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect accelerator pedal position (APP) sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between APP sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 6.
NO >> GO TO 2.
2.CHECK SENSOR POWER SUPPLY CIRCUIT
Check harness for short to power and short to ground, between the following terminals.
DTC No.Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0643 SENSOR POWER/CIRC
(Sensor power su
pply circuit
short) ECM detects that the voltage of
power source for sensor is ex-
cessively low or high.  Harness or connectors
(Accelerator pedal position sensor 1 circuit is shorted.)
[Camshaft position sensor (bank 2) circuit is shorted.]
[Manifold absolute pressure (MAP) sensor circuit is
shorted.]
(Throttle position sensor circuit is shorted.)
 Accelerator pedal position sensor 1
 Camshaft position sensor (bank 2)
 Manifold absolute pressure (MAP) sensor
 Throttle position sensor
APP sensor Ground Voltage (V)
Connector Terminal
E110 (Without ICC) 2 Ground Approx. 5
E67 (With ICC) 12
Revision: 2010 May2011 QX56

EC-384
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0850 PNP SWITCH
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to
EC-384, "Diagnosis Procedure".
NO >> INSPECTION END
5.PERFORM COMPONENT FUNCTION CHECK
WITH GST
Perform Component Function Check. Refer to EC-384, "
Component Function Check".
NOTE:
Use Component Function Check to check the overall func tion of the park/neutral position (PNP) signal circuit.
During this check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-384, "
Diagnosis Procedure".
Component Function CheckINFOID:0000000006217886
1.PERFORM COMPONENT FUNCTION CHECK
WITH GST
1. Turn ignition switch ON.
2. Check the voltage between ECM harness connector terminals under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-384, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006217887
1.CHECK DTC WITH TCM
Refer to TM-61, "
CONSULT-III Function (TRANSMISSION)".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace malfunctioning part.
2.CHECK STARTING SYSTEM
Turn ignition switch OFF, then turn it to START.
Does starter motor operate?
YES >> GO TO 3.
NO >> Check DTC with BCM. Refer to BCS-57, "
DTCIndex".
3.CHECK PNP SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect A/T assembly harness connector.
3. Disconnect ECM harness connector.
4. Check the continuity between A/T assembly harness connector and ECM harness connector.
VHCL SPEED SE More than 64 km/h (40 mph)
Selector lever Suitable position
ECM
Condition Voltage (V)
Connector +–
Te r m i n a l Te r m i n a l
F111 11 175 Selector lever P or N position Battery voltage
Except above position Approx. 0
Revision: 2010 May2011 QX56

P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR
EC-387
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P1089, P1092 VVEL CONTROL
SHAFT POSITION SENSOR
DTC LogicINFOID:0000000006217894
DTC DETECTION LOGIC
NOTE:
If DTC P1089 or P1092 is displayed with DTC P1608, first perform the trouble diagnosis for DTC P1608.
Refer to EC-453, "
DTC 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, confi rm that battery voltage is 10 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for 1 second.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-387, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217895
1.VVEL CONTROL SHAFT POSITION SENSOR POWER SUPPLY CIRCUIT
1. Disconnect VVEL control shaft pos ition sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between VVEL control shaf t position sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1089 VVEL POS SEN/CIRC-B1
[VVEL control shaf
t position sen-
sor (bank 1) circuit]  An excessively low voltage from the sensor
is sent to VVEL control module.
 An excessively high voltage from the sensor is sent to VVEL control module.
 Rationally incorrect voltage is sent to VVEL control module compared with the signals
from VVEL control shaft position sensor 1
and VVEL control shaft position sensor 2.  Harness or connectors
(VVEL control shaft position sen-
sor circuit is open or shorted.)
 VVEL control shaft position sen- sor
 VVEL control module
P1092 VVEL POS SEN/CIRC-B2
[VVEL control shaf
t position sen-
sor (bank 2) circuit]
DTC No. VVEL control shaft position sensor
Ground Voltage (V)
Bank Connector Terminal
P1089 1 F72 3
Ground Approx. 5
6
P1092 2 F70 3
6
Revision: 2010 May2011 QX56

EC-390
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1090, P1093 VVEL ACTUATOR MOTOR
P1090, P1093 VVEL ACTUATOR MOTOR
DTC LogicINFOID:0000000006217896
DTC DETECTION LOGIC
NOTE:
If DTC P1090 or P1093 is displayed with DTC P1091,
first perform the trouble diagnosis for DTC P1091.
Refer to EC-393, "
DTC 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, confi rm that battery voltage is 10 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for 10 second.
2. Keep the engine speed at approximately 3,500 rpm for at least 10 seconds under no load.
3. Check DTC.
Is DTC detected?
YES >> Go to EC-390, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217897
1.VVEL ACTUATOR MOTOR ASSEMBLY OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect VVEL control module harness connector.
2. Disconnect VVEL actuator motor assembly harness connector.
3. Check the continuity between VVEL control modul e harness connector and VVEL actuator motor assem-
bly harness connector.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1090 VVEL ACTR MOT-B1
[VVEL system performance
(bank 1)]
 Event angle difference between the
actual and the target is detected.
 Abnormal current is sent to VVEL actuator motor assembly.  Harness or connectors
(VVEL actuator motor assembly circuit is open
or shorted.)
 VVEL actuator motor assembly
 VVEL actuator housing assembly
 VVEL ladder assembly
 VVEL control module
P1093
VVEL ACTR MOT-B2
[VVEL system performance
(bank 2)]
DTC No.
VVEL control module VVEL ac
tuator motor assembly
Continuity
Bank Connector Terminal Connector Terminal
P1090 1 F5612
F73 1Existed
2 Not existed
25 1 Not existed
2Existed
P1093 2 2
F71 1Existed
2 Not existed
15 1 Not existed
2Existed
Revision: 2010 May2011 QX56

P1091 VVEL ACTUATOR MOTOR RELAYEC-393
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P1091 VVEL ACTUATOR MOTOR RELAY
DTC LogicINFOID:0000000006217900
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, confi rm that battery voltage is 10 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON and wait at least 1 seconds.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and wait at least 1 seconds.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-393, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217901
1.VVEL ACTUATOR MOTOR RELAY POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect VVEL actuator motor relay.
3. Check the voltage between VVEL actuator motor relay harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
 50A fusible link (letter O)
 Harness for open or short between VVEL actuator motor relay and battery
>> Repair open circuit, short to ground or short to power in harness or connectors.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1091 VVEL ACTR MOT PWR
[VVEL actuator motor relay
circuit]  VVEL control module detects the VVEL
actuator motor relay is stuck OFF.
 VVEL control module detects the VVEL actuator motor relay is stuck ON.  Harness or connectors
(VVEL actuator motor rela y circuit is open or
shorted.)
(Abort circuit is open or shorted.)
 VVEL actuator motor relay
 VVEL control module
ECM
VVEL actuator motor relay Ground Voltage
Connector Terminal
E62 1
Ground Battery voltage
3
Revision: 2010 May2011 QX56