2011 INFINITI QX56 engine

P0527 COOLING FAN SPEED SENSOREC-367
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0527 COOLING FAN SPEED SENSOR
DTC LogicINFOID:0000000006217867
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 engine and warm it up to the normal operating temperature.
2. Keep the engine speed approximately 1,000 rpm at no load.
3. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-367, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217868
1.CHECK COOLING FAN SPEED SENSOR POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect electrically-controlled c ooling fan coupling harness connector.
3. Turn ignition switch ON.
4. Check the voltage between electrically-controlled cooling fan coupling harness connector terminals.
Is inspection result normal?
YES >> GO TO 6.
NO >> GO TO 2.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0527 Cooling fan speed sen-
sor circuit range/perfor-
mance The number of fan speed signals is 16 rpm or
less during engine rev.  Harness or connectors
(The Fuel rail pressure sensor circuit is
open or shorted.)
(The Power steering pressure sensor cir-
cuit is open or shorted)
(The Electrically-controlled cooling fan
coupling circuit is open or shorted)
 Fuel rail pressure sensor
 Power steering pressure sensor
 Cooling fan speed sensor
 Electrically-controlled cooling fan cou- pling
 Cooling fan
 IPDM E/R
Electrically-controlled cooling fan coupling Vo l ta g e
(Approx.)
Connector +
−
terminal
F39 2 4 5 V
Revision: 2010 May2011 QX56

P0550 PSP SENSOREC-371
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0550 PSP SENSOR
DTC LogicINFOID:0000000006217870
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. Start engine and let it idle for at least 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-371, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217871
1.CHECK POWER STEERING PRESSURE SENSOR POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect power steering pressure (PSP) sensor harness connector.
3. Turn ignition switch ON.
4. Check the voltage between PSP sensor harness connector terminals.
Is the inspection result normal?
YES >> GO TO 6.
NO >> GO TO 2.
2.CHECK POWER STEERING PRESSURE SENSOR POWER SUPPLY CIRCUIT-II
1. Check the voltage between PSP sensor harness connector and the ground.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0550 PW ST P SEN/CIRC
(Power steering pressure
sensor circuit) An excessively low or high voltage from the
sensor is sent to ECM.  Harness or connectors
(The Fuel rail pressure sensor circuit is
open or shorted.)
(The Power steering pressure sensor cir-
cuit is open or shorted)
(The Electrically-controlled cooling fan
coupling circuit is open or shorted)
 Fuel rail pressure sensor
 Power steering pressure sensor
 Electrically-controlled cooling fan cou- pling
PSP sensor Vo l ta g e
(Approx.)
Connector +
−
terminal
F35 1 3 5 V
Revision: 2010 May2011 QX56

P0550 PSP SENSOREC-373
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NO >> Repair or replace error-detected parts.
6.CHECK PSP SENSOR SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between PSP sens or harness connector and ECM harness connector.
4. Also check harness for short to ground and to power.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Repair or replace error-detected parts.
7.CHECK PSP SENSOR
Refer to EC-373, "
Component Inspection (Power Steering Pressure Sensor)".
Is the inspection result normal?
YES >> GO TO 8.
NO >> Replace PSP sensor.
8.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (Power Steering Pressure Sensor)INFOID:0000000006217872
1.CHECK POWER STEERING PRESSURE SENSOR
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Start engine and let it idle.
4. Check the voltage between ECM harness connector terminals under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace power steering pressure sensor.
+ −
Continuity
PSP sensor ECM
Connector Terminal Connector Terminal F35 2 F111 39 Existed
ECM Condition Voltage (V)
Connector +–
Te r m i n a l Te r m i n a l
F111 39 45 Steering wheel Being turned 0.5 - 4.5
Not being turned 0.4 - 0.8
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]
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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

P0850 PNP SWITCHEC-383
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0850 PNP SWITCH
DescriptionINFOID:0000000006217884
When the selector lever position is P or N, park/neut
ral position (PNP) signal is sent to ECM from TCM.
DTC LogicINFOID:0000000006217885
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.INSPECTION START
Will CONSULT-III be used?
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 5.
2.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 3.
3.CHECK PNP SIGNAL
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “P/N POSI SW” in “DATA MONITOR” mode wit h CONSULT-III. Then check the “P/N POSI SW” sig-
nal under the following conditions.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Go to EC-384, "
Diagnosis Procedure".
4.PERFORM DTC CONFIRMATION PROCEDURE
1. Select “DATA MONITOR” mode with CONSULT-III.
2. Start engine and warm it up to normal operating temperature.
3. Maintain the following conditions for at least 50 consecutive seconds. CAUTION:
Always drive vehicle at a safe speed.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0850 P-N POS SW/CIRCUIT
(Park/neutral position
switch) The signal of the park/neutral position (PNP)
signal does not change during driving after the
engine is started.  Harness or connectors
[The park/neutral position (PNP) signal
circuit is open or shorted.]
TCM
Position (Selector lever) Known-good signal
N or P position ON
Except above position OFF
ENG SPEED 1,300 - 6,375 rpm
COOLAN TEMP/S More than 70 °C (158 °F)
B/FUEL SCHDL 2.0 - 31.8 msec
Revision: 2010 May2011 QX56

P1089, P1092 VVEL CONTROL SHAFT POSITION SENSOR
EC-387
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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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