ignition INFINITI QX56 2009 Factory Service Manual

EC-286
< COMPONENT DIAGNOSIS >[VK56DE]
P0643 SENSOR POWER SUPPLY
NG >> Repair or replace ground connections.
2.CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect accelerator pedal position (APP) sensor harness connector.
2. Turn ignition switch ON.
3. Check voltage between APP sensor terminal 7 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 3.
3.CHECK SENSOR POWER SUPPLY CIRCUITS
Check harness for short to power and short to ground, between the following terminals
OK or NG
OK >> GO TO 4.
NG >> Repair short to ground or short to power in harness or connectors.
4.CHECK COMPONENTS
Check the following.
 EVAP control system pressure sensor (Refer to EC-244, "Component Inspection"
.)
 Power steering pressure sensor (Refer to EC-279, "Component Inspection"
.)
 Battery current sensor (Refer to EC-310, "Component Inspection"
.)
 Refrigerant pressure sensor
OK or NG
OK >> GO TO 7.
NG >> Replace malfunctioning components.
5.CHECK ACCELERATOR PEDAL POSITION SENSOR
Refer to EC-376, "Component Inspection"
.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
BBIA0361E
Voltage: Approximately 5V
JMBIA0601ZZ
ECM terminal Sensor terminal Reference Wiring Diagram
48 EVAP control system pressure sensor terminal 3
EC-432, "Wiring Diagram - ENGINE
CONTROL SYSTEM -"
49Refrigerant pressure sensor terminal 1
Battery current sensor terminal 1
68 Power steering pressure sensor terminal 1
90 APP sensor terminal 7
Revision: December 20092009 QX56

EC-288
< COMPONENT DIAGNOSIS >[VK56DE]
P0850 PNP SWITCH
P0850 PNP SWITCH
Component DescriptionINFOID:0000000003771570
When the selector lever position is P or N, trans
mission range signal from the TCM is sent to ECM.
On Board Diagnosis LogicINFOID:0000000003771571
DTC Confirmation ProcedureINFOID:0000000003771572
CAUTION:
Always drive vehicle at a safe speed.
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
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.
If NG, go to EC-289, "Diagnosis Procedure"
.
If OK, go to following step.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Start engine and warm it up to normal operating temperature.
5. Maintain the following conditions for at least 60 consecutive seconds.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to EC-289, "Diagnosis Procedure"
.
Overall Function CheckINFOID:0000000003771573
Use this procedure to check the overall function of t he transmission range signal circuit. During this check, a
1st trip DTC might not be confirmed.
WITH GST
1. Turn ignition switch ON.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0850
0850 Park/neutral position
switch The transmission range signal is not changed in
the process of engine starting and driving.  Harness or connectors
[The transmission range signal circuit is
open or shorted.]
 Combination meter
TCM
Position (Selector lever) Known-good signal
N or P position ON
Except the above position OFF
ENG SPEED 1,000 - 6,375 rpm
COOLAN TEMP/S More than 70 °C (158 °F)
B/FUEL SCHDL 2.0 - 31.8 msec
VHCL SPEED SE More than 64 km/h (40 MPH)
Selector lever Suitable position
Revision: December 20092009 QX56

P0850 PNP SWITCHEC-289
< COMPONENT DIAGNOSIS > [VK56DE]
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2. Check voltage between ECM terminal 102 (transmission range
signal) and ground under the following conditions.
3. If NG, go to EC-289, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771574
1.CHECK DTC WITH TCM
Refer to TM-30, "OBD-II Diagnostic Trouble Code (DTC)"
.
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2.CHECK STARTING SYSTEM
Turn ignition switch OFF, then turn it to START.
Does starter motor operate?
Ye s o r N o
Yes >> GO TO 3.
No >> Refer to STR-18
.
3.CHECK TRANSMISSION RANGE INPUT SI GNAL CIRCUIT FOR OPEN AND SHORT-I
1. Turn ignition switch OFF.
2. Disconnect A/T assembly harness connector.
3. Disconnect combination meter harness connector.
4. Check harness continuity between A/T assembly terminal 9 and combination meter terminal 8. Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors F14, E5
 Harness connectors E152, M31
 Harness for open or short between A/T assembly and combination meter
>> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK TRANSMISSION RANGE INPUT SI GNAL CIRCUIT FOR OPEN AND SHORT-II
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 102 and combination meter terminal 7. Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
Condition (Gear position) Voltage (Known-good data)
P or N position Approx. 0
Except the above position BATTERY VOLTAGE
(11 - 14V)
MBIB0043E
Continuity should exist.
Continuity should exist.
Revision: December 20092009 QX56

P1140, P1145 IVT CONTROL POSITION SENSOR
EC-291
< COMPONENT DIAGNOSIS > [VK56DE]
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P1140, P1145 IVT CONTROL POSITION SENSOR
Component DescriptionINFOID:0000000003771575
Intake valve timing control position sensors are located in the front of
cylinder heads in both bank 1 and bank 2.
This sensor uses a Hall IC.
The cam position is determined by the intake camshaft sprocket con-
cave (in four places). The ECM provides feedback to the intake valve
timing control for appropriate target valve open-close timing accord-
ing to drive conditions based on detected cam position.
On Board Diagnosis LogicINFOID:0000000003771576
DTC Confirmation ProcedureINFOID:0000000003771577
1. If DTC Confirmation Procedure has been previously c
onducted, always perform the following before con-
ducting the next step.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Turn ignition switch ON.
c. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Maintain the following conditions for at least 10 seconds.
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to EC-291, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771578
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
SEF359Z
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1140
11 4 0
(Bank 1)
Intake valve timing control
position sensor circuit An excessively high or low voltage from the
sensor is sent to ECM.  Harness or connectors
(Intake valve timing control position
sensor circuit is open or shorted)
 Intake valve timing control position sensor
 Crankshaft position sensor (POS)
 Camshaft positi on sensor (PHASE)
 Accumulation of debris to the signal pick-up portion of the camshaft sprock-
et
P1145
11 4 5
(Bank 2)
ENG SPEED More th
an idle speed
Selector lever P or N position
Revision: December 20092009 QX56

EC-292
< COMPONENT DIAGNOSIS >[VK56DE]
P1140, P1145 IVT CONT
ROL POSITION SENSOR
Refer to EC-85, "Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK INTAKE VALVE TIMING CONTROL PO SITION SENSOR POWER SUPPLY CIRCUIT
1. Disconnect intake valve timing control position sensor harness connector.
2. Turn ignition switch ON.
3. Check voltage between intake valve timing control position sen- sor 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 E2, F32
 Harness for open or short between intake valve timing control position sensor and IPDM E/R
 Harness for open or short between intake va lve timing control position sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK INTAKE VALVE TIMING CONTROL POSI TION SENSOR GROUND CIRCUIT FOR OPEN AND
SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between intake valve timing control position sensor terminal 1 and ground.
Refer to Wiring Diagram.
BBIA0354E
1. Intake valve timing control position
sensor (bank 2) 2. Intake valve timing control solenoid
valve (bank 2) 3. Drive belt
4. Radiator hose 5. Intake valve timing control solenoid valve (bank 1)6. Intake valve timing control position
sensor (bank 1)
Voltage: Battery voltage
BBIA0771E
PBIB2613E
Revision: December 20092009 QX56

EC-298
< COMPONENT DIAGNOSIS >[VK56DE]
P1217 ENGINE OVER TEMPERATURE
P1217 ENGINE OVER TEMPERATURE
On Board Diagn
osis LogicINFOID:0000000003771589
NOTE:
If DTC P1217 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-86
.
 If DTC P1217 is displayed with DTC P0607, first pe rform the trouble diagnosis for DTC P0607. Refer
to EC-284
.
If the cooling fan or another component in the coo ling system malfunctions, engine coolant temperature will
rise.
When the engine coolant temperature reaches an abnorma lly high temperature condition, a malfunction is
indicated.
This self-diagnosis has the one trip detection logic.
CAUTION:
When a malfunction is indicated, be su re to replace the coolant. Refer to CO-11, "Changing Engine
Coolant". Also, replace the engine oil. Refer to LU-9, "Changing Engine Oil".
1. Fill radiator with coolant up to specified level with a filling speed of 2 liters per minute. Be sure to
use coolant with the proper mixture ratio. Refer to CO-10
.
2. After refilling coolant, run engine to en sure that no water-flow noise is emitted.
Overall Function CheckINFOID:0000000003771590
Use this procedure to check the overall function of the cooling fan. During this check, a DTC might not be con-
firmed.
WARNING:
Never remove the radiator cap and/or reservoir tank cap when the engine is hot. Serious burns could
be caused by high pressure fluid escaping fr om the radiator and/or reservoir tank.
Wrap a thick cloth around cap. Carefully remove the cap by turning it a quarter turn to allow built-up
pressure to escape. Then turn the cap all the way off.
WITH CONSULT-III
1. Check the coolant level in the reservoir tank and radiator. Allow engine to cool before checking coolant level.
If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to EC-388,
"Diagnosis Procedure".
2. Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to EC-388,
"Diagnosis Procedure".
3. Turn ignition switch ON.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1217
1217 Engine over tempera-
ture (Overheat)  Cooling fan does not operate properly (Over-
heat).
 Cooling fan system does not operate proper-
ly (Overheat).
 Engine coolant was not added to the system using the proper filling method.
 Engine coolant is not within the specified range.  Harness or connectors
(The cooling fan circuit is open or short-
ed.)
 Cooling fan
 Cooling fan (crankshaft diven)
 IPDM E/R (Cooling fan relay)
Radiator hose
Radiator
Radiator cap
 Reservoir tank
 Reservoir tank cap
 Water pump
Thermostat
For more informat ion, refer to EC-300,
"Main 13 Causes of Overheating".
SEF621W
Revision: December 20092009 QX56

P1217 ENGINE OVER TEMPERATUREEC-301
< COMPONENT DIAGNOSIS > [VK56DE]
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*1: Turn the ignition switch ON.
*2: Engine running at 3,000 rpm for 10 minutes.
*3: Drive at 90 km/h (55 MPH) for 30 minutes and then let idle for 10 minutes.
*4: After 60 minutes of cool down time.
For more information, refer to
CO-8, "Troubleshooting Chart"
.
OFF 8  Combustion gas leak  Color checker chemical
tester 4 Gas analyzerNegative —
ON*
39  Coolant temperature gauge  Visual Gauge less than 3/4 when
driving —
 Coolant overflow to res- ervoir tank  Visual No overflow during driving
and idling CO-11, "Changing Engine
Coolant"
OFF*410  Coolant return from res-
ervoir tank to radiator  Visual Should be initial level in
reservoir tank CO-11, "Changing Engine
Coolant"
OFF 12  Cylinder head  Straight gauge feeler
gauge0.1 mm (0.004 in) Maxi-
mum distortion (warping) EM-72, "Inspection After
Disassembly"
13  Cylinder block and pis-
tons  Visual No scuffing on cylinder
walls or piston EM-90, "Inspection After
Disassembly"
Engine Step Inspection item Equipment Standard Reference page
Revision: December 20092009 QX56

EC-302
< COMPONENT DIAGNOSIS >[VK56DE]
P1225 TP SENSOR
P1225 TP SENSOR
Component DescriptionINFOID:0000000003771593
Electric throttle control actuator
consists of throttle control motor,
throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has t he two sensors. These sensors are
a kind of potentiometers which transform the throttle valve position
into output voltage, and emit the voltage signal to the ECM. In addi-
tion, these sensors detect the opening and closing speed of the
throttle valve and feed the voltage signals to the ECM. The ECM
judges the current opening angle of the throttle valve from these sig-
nals and the ECM controls the throttle control motor to make the
throttle valve opening angle properly in response to driving condi-
tion.
On Board Diagn osis LogicINFOID:0000000003771594
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000003771595
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 procedure, confirm that battery voltage is more than 10V at idle.
1. Turn ignition switch ON.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Check 1st trip DTC.
5. If 1st trip DTC is detected, go to EC-302, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771596
1.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
1. Turn ignition switch OFF.
2. Remove the intake air duct.
3. Check if foreign matter is caught between the throttle valve and the housing.
OK or NG
OK >> GO TO 2.
NG >> Remove the foreign matter and clean the electric throttle control actuator inside.
2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
PBIB0145E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1225
1225 Closed throttle position learning
performance Closed throttle position learning value is
excessively low.  Electric throttle control actuator
(TP sensor 1 and 2)
BBIA0364E
Revision: December 20092009 QX56

EC-304
< COMPONENT DIAGNOSIS >[VK56DE]
P1226 TP SENSOR
P1226 TP SENSOR
Component DescriptionINFOID:0000000003771597
Electric throttle control actuator
consists of throttle control motor,
throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has t he two sensors. These sensors are
a kind of potentiometers which transform the throttle valve position
into output voltage, and emit the voltage signal to the ECM. In addi-
tion, these sensors detect the opening and closing speed of the
throttle valve and feed the voltage signals to the ECM. The ECM
judges the current opening angle of the throttle valve from these sig-
nals and the ECM controls the throttle control motor to make the
throttle valve opening angle properly in response to driving condi-
tion.
On Board Diagn osis LogicINFOID:0000000003771598
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000003771599
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:
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
1. Turn ignition switch ON.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Repeat steps 2 and 3 for 32 times.
5. Check 1st trip DTC.
6. If 1st trip DTC is detected, go to EC-304, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771600
1.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
1. Turn ignition switch OFF.
2. Remove the intake air duct.
3. Check if foreign matter is caught between the throttle valve and the housing.
OK or NG
OK >> GO TO 2.
NG >> Remove the foreign matter and clean the electric throttle control actuator inside.
PBIB0145E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1226
1226 Closed throttle position learning
performance Closed throttle position learning is not performed
successfully, repeatedly.  Electric throttle control actuator
(TP sensor 1 and 2)
BBIA0364E
Revision: December 20092009 QX56

EC-306
< COMPONENT DIAGNOSIS >[VK56DE]
P1421 COLD START CONTROL
P1421 COLD START CONTROL
DescriptionINFOID:0000000003771601
ECM controls ignition timing and engine idle speed when engine is started with prewarming up condition.
This control promotes the activation of three way ca
talyst by heating the catalyst and reduces emissions.
On Board Diagnosis LogicINFOID:0000000003771602
DTC Confirmation ProcedureINFOID:0000000003771603
NOTE:
 If DTC Confirmation Procedure has been previously conducted, always perform the following before con-
ducting 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.
 If DTC P1421 is displayed with other DTC, firs t perform the trouble diagnosis for other DTC.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-IIl.
4. Check that the “COOLAN TEMP/S” indication is between 4 °C (39 °F) and 36 °C (97 °F).
If “COOLAN TEMP/S” indication is within t he specified value, go to the following step.
If “COOLANT TEMP/S” indication is out of the s pecified value, cool engine down or warm engine up and
go to step 1.
5. Start engine and let it idle for 5 minutes.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to EC-306, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771604
1.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-18, "Idle Air Volume Learning"
.
Is Idle Air Volume Lear ning carried out successfully?
Ye s o r N o
Ye s > > G O T O 2 .
No >> Follow the instruction of Idle Air Volume Learning.
2.CHECK INTAKE SYSTEM
Check for the cause of intake air volume lacking. Refer to the following.
 Crushed intake air passage
 Intake air passage clogging
OK or NG
OK >> GO TO 3.
NG >> Repair or replace malfunctioning part
3.CHECK FUEL INJECTION SYSTEM FUNCTION
Perform EC-169, "DTC Confirmation Procedure"
in DTC P0171, P0174 FUEL INJECTION SYSTEM FUNC-
TION.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1421
1421 Cold start emission reduction
strategy monitoring ECM does not control ignition timing and engine
idle speed properly when engine is started with
prewarming up condition.  Lack of intake air volume
 Fuel injection system
ECM
Revision: December 20092009 QX56