INFINITI QX56 2008 Factory Service Manual

EC-302
< COMPONENT DIAGNOSIS >[VK56DE]
P1140, P1145 IVT CONTROL POSITION SENSOR
>>
INSPECTION END
Component InspectionINFOID:0000000001351701
INTAKE VALVE TIMING CONTROL POSITION SENSOR
1. Disconnect intake valve timing control position sensor harness connector.
2. Loosen the fixing bolt of the sensor.
3. Remove the sensor.
4. Visually check the sensor for chipping.
5. Check resistance as shown below.
6. If NG, replace intake valve timing control position sensor. Refer
to EC-501
.
SEF362Z
Terminal No. (Polarity) Resistance Ω [at 25 °C (77 °F)]
3 (+) - 1 (-) Except 0 or ∞
2 (+) - 1 (-)
3 (+) - 2 (-)
PBIB0194E
Revision: March 2010 2008 QX56

P1148, P1168 CLOSED LOOP CONTROLEC-303
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P1148, P1168 CLOSED LOOP CONTROL
On Board Diagnosis LogicINFOID:0000000001351703
These self-diagnoses have the on
e trip detection logic.
DTC P1148 or P1168 is displayed with another DTC for air fuel ratio (A/F) sensor 1.
Perform the trouble diagnosis for the corresponding DTC.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1148
11 4 8
(Bank 1) Closed loop control
function The closed loop control function for bank 1 does
not operate even when vehicle is driving in the
specified condition.
• Harness or connectors
[The air fuel ratio (A/F) sensor 1 circuit is
open or shorted.]
• Air fuel ratio (A/F) sensor 1
• Air fuel ratio (A/F) sensor 1 heater
P1168
11 6 8
(Bank 2) The closed loop control function for bank 2 does
not operate even when vehicle is driving in the
specified condition.
Revision: March 2010
2008 QX56

EC-304
< COMPONENT DIAGNOSIS >[VK56DE]
P1211 TCS CONTROL UNIT
P1211 TCS CONTROL UNIT
DescriptionINFOID:0000000001351704
The malfunction information related to TCS is trans
ferred through the CAN communication line from “ABS
actuator and electric unit (control unit)” to ECM.
Be sure to erase the malfunction information such as DTC not only for “ABS actuator and electric unit
(control unit)” but also for ECM after TCS related repair.
On Board Diagn osis LogicINFOID:0000000001351705
Freeze frame data is not stored in the ECM for this self-diagnosis.
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000001351706
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.
WITH CONSULT-III
1. Start engine and let it idle for at least 60 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-304, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351707
Go to BRC-24, "CONSULT-III Function (ABS)".
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1211
1211 TCS control unit
ECM receives a malfunction information from
“ABS actuator electric
unit (control unit)” • ABS actuator and electric unit (control
unit)
• TCS related parts
Revision: March 2010 2008 QX56

P1212 TCS COMMUNICATION LINEEC-305
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P1212 TCS COMMUNICATION LINE
DescriptionINFOID:0000000001351708
NOTE:
•
If DTC P1212 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-87
.
• If DTC P1212 is displayed with DTC U1010, first pe rform the trouble diagnosis for DTC U1010. Refer
to EC-88
.
This CAN communication line is used to control the smooth engine operation during the TCS operation. Pulse
signals are exchanged between ECM and “ABS actuator and electric unit (control unit)”.
Be sure to erase the malf unction information such as DTC not onl y for “ABS actuator and electric unit
(control unit)” but also for ECM after TCS related repair.
On Board Diagnosis LogicINFOID:0000000001351709
Freeze frame data is not stored in the ECM for this self-diagnosis.
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000001351710
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.
WITH CONSULT-III
1. Start engine and let it idle for at least 10 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-305, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001351711
Go to BRC-24, "CONSULT-III Function (ABS)".
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1212
1212 TCS communication line ECM can not receive the information from
“ABS actuator and electric unit (control
unit)” continuously. • Harness or connectors
(The CAN communication line is open or short-
ed.)
• ABS actuator and electric unit (control unit)
• Dead (Weak) battery
Revision: March 2010 2008 QX56

EC-306
< COMPONENT DIAGNOSIS >[VK56DE]
P1217 ENGINE OVER TEMPERATURE
P1217 ENGINE OVER TEMPERATURE
On Board Diagn
osis LogicINFOID:0000000001351714
NOTE:
•If DTC P1217 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-87
.
• If DTC P1217 is displayed with DTC U1010, first pe rform the trouble diagnosis for DTC U1010. Refer
to EC-88
.
If the cooling fan or another component in the cooling 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 sure 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:0000000001351715
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-395,
"Diagnosis Procedure".
2. Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to EC-395,
"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-308,
"Main 13 Causes of Overheating".
SEF621W
Revision: March 2010 2008 QX56

P1217 ENGINE OVER TEMPERATUREEC-307
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
4. Perform “COOLING FAN” in “ACTIVE TEST” mode with CONSULT-III.
5. If the results are NG, go to
EC-395, "
Diagnosis Procedure".
WITH GST
1. Check the coolant level in the reservoir tank and radiator.
Allow engine to cool befo re 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-395,
"Diagnosis Procedure".
2. Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to EC-395,
"Diagnosis Procedure".
3. Disconnect engine coolant temper ature sensor harness connec-
tor.
4. Connect 150Ω resistor to engine coolant temperature sensor
harness connector.
5. Start engine and make sure that cooling fan operates. CAUTION:
Be careful not to overheat engine.
6. If NG, go to EC-395, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000001351717
1.CHECK COOLING FAN (CRANKSHAFT DRIVEN) OPERATION
1. Start engine and let it idle.
2. Make sure that cooling fan (crankshaft driven) operates normally.
OK or NG
OK (With CONSULT-III)>>GO TO 2.
OK (Without CONSULT-III)>>GO TO 3.
NG >> Check cooling fan (crankshaft driven). Refer to CO-18, "
Removal and Installation (Crankshaft
Driven Type)".
2.CHECK COOLING FAN MOTOR OPERATION
With CONSULT-III
1. Start engine and let it idle.
2. Select “COOLING FAN” in “ACTIVE TEST” mode with CONSULT-III.
3. Make sure that cooling fan operates.
OK or NG
OK >> GO TO 4.
NG >> Check cooling fan control ci rcuit. (Go to "PROCEDURE A".)
3.CHECK COOLING FAN MOTOR OPERATION
Without CONSULT-III
1. Disconnect engine coolant temperature sensor harness connector.
2. Connect 150Ω resistor to engine coolant temperature sensor harness connector.
3. Start engine and let it idle.
SEF621W
SEF882V
Revision: March 2010 2008 QX56

EC-308
< COMPONENT DIAGNOSIS >[VK56DE]
P1217 ENGINE OVER TEMPERATURE
4. Make sure that cooling fan operates.
OK or NG
OK >> GO TO 4.
NG >> Check cooling fan control circuit. (Go to "PROCEDURE
A".)
4.CHECK COOLING SYSTEM FOR LEAK
Refer to CO-10, "
Inspection".
OK or NG
OK >> GO TO 5.
NG >> Check the following for leak. •Hose
• Radiator
• Radiator cap
• Water pump
• Reservoir tank
5.CHECK COMPONENT PARTS
Check the following.
• RESERVOIR TANK CAP (Refer to CO-10, "
Inspection".)
• Thermostat. (Refer to CO-22, "
Removal and Installation".)
• Engine coolant temperature sensor. (Refer to EC-126, "
Component Inspection".)
OK or NG
OK >> GO TO 6.
NG >> Replace malfunctioning component.
6.CHECK MAIN 13 CAUSES
If the cause cannot be isolated, go to EC-308, "
Main 13 Causes of Overheating".
>> INSPECTION END
Main 13 Causes of OverheatingINFOID:0000000001351718
SEF882V
Engine Step Inspection item EquipmentStandardReference page
OFF 1 • Blocked radiator • Blocked condenser
• Blocked radiator grille
• Blocked bumper • Visual
No blocking —
2 • Coolant mixture • Coolant tester 50 - 50% coolant mixtureCO-10
3 • Coolant level • VisualCoolant up to MAX level in
reservoir tank and radiator
filler neck CO-11, "Changing Engine
Coolant"
4 • Reservoir tank cap • Pre
ssure tester 95 - 125 kPa
(0.97 - 1.28 kg/cm2, 14 -
18 psi) (Limit) CO-10, "
Inspection"
ON*25 • Coolant leaks
• VisualNo leaks CO-10, "Inspection"
ON*26 • Thermostat • Touch the upper and
lower radiator hoses Both hoses should be hot
CO-22, "Removal and In-
stallation"
ON*17 • Cooling fan • CONSULT-IIIOperating See trouble diagnosis for
DTC P1217 ( EC-36
).
Revision: March 2010 2008 QX56

P1217 ENGINE OVER TEMPERATUREEC-309
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
*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
gauge 0.1 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
EquipmentStandardReference page
Revision: March 2010 2008 QX56

EC-310
< COMPONENT DIAGNOSIS >[VK56DE]
P1225 TP SENSOR
P1225 TP SENSOR
Component DescriptionINFOID:0000000001351876
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 the 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:0000000001351877
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000001351878
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
WITH CONSULT-lll
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-310, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-lll” above.
Diagnosis ProcedureINFOID:0000000001351879
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 conditionPossible 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: March 2010 2008 QX56

P1225 TP SENSOREC-311
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2.REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
1. Replace the electric throttle control actuator.
2. Perform EC-18, "
Throttle Valve Closed Position Learning".
3. Perform EC-18, "
Idle Air Volume Learning".
>> INSPECTION END
Revision: March 2010 2008 QX56