2007 INFINITI QX56 DTC

EC-474
< SERVICE INFORMATION >
DTC P1217 ENGINE OVER TEMPERATURE
OK (Without CONSULT-II)>>GO TO 3.
NG >> Check cooling fan (crankshaft driven). Refer to CO-16, "
Removal and Installation (Crankshaft
Driven Type)".
2.CHECK COOLING FAN MOTOR OPERATION
With CONSULT-II
1. Start engine and let it idle.
2. Select “COOLING FAN” in “ACTIVE TEST” mode with CON-
SULT-II.
3. Make sure that cooling fan operates.
OK or NG
OK >> GO TO 4.
NG >> Check cooling fan control circuit. (Go to "PROCEDURE
A".)
3.CHECK COOLING FAN MOTOR OPERATION
Without CONSULT-II
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.
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-9, "
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-9, "
Inspection".)
• Thermostat. (Refer to CO-20
.)
• Engine coolant temperature sensor. (Refer to EC-209, "
Component Inspection".)
OK or NG
OK >> GO TO 7.
NG >> Replace malfunctioning component.
6.CHECK MAIN 13 CAUSES
If the cause cannot be isolated, go to EC-476, "
Main 13 Causes of Overheating".
SEF646X
SEF882V

DTC P1217 ENGINE OVER TEMPERATURE
EC-475
< SERVICE INFORMATION >
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>>INSPECTION END
PROCEDURE A
1.CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness connector E120.
3. Check voltage between IPDM E/R terminal 22 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
• 40A fusible link
• Harness for open or short between IPDM E/R and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
3.CHECK COOLING FAN MOTOR CIRCUIT FOR OPEN OR SHORT
1. Disconnect cooling fan motor harness connector (1).
2. Check harness continuity between cooling fan motor terminal 1
and IPDM E/R terminal 24, cooling fan motor terminal 2 and
ground.
Refer to wiring diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
4.CHECK COOLING FAN MOTOR
Refer to EC-476, "
Component Inspection".
OK or NG
OK >> GO TO 5.
NG >> Replace cooling fan motor.
5.CHECK INTERMITTENT INCIDENT
Perform EC-138
.
OK or NG
OK >> Replace IPDM E/R. Refer to PG-28, "Removal and Installation of IPDM E/R".
NG >> Repair or replace harness connectors.Voltage: Battery voltage
PBIB2067E
Continuity should exist.
BBIA0742E

EC-476
< SERVICE INFORMATION >
DTC P1217 ENGINE OVER TEMPERATURE
Main 13 Causes of Overheating
INFOID:0000000003531995
*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-6
.
Component InspectionINFOID:0000000003531996
COOLING FAN MOTOR
1. Disconnect cooling fan motor harness connector.
2. Supply cooling fan motor terminals with battery voltage and
check operation.
Cooling fan motor should operate.
If NG, replace cooling fan motor.
Engine Step Inspection item Equipment Standard Reference page
OFF 1 • Blocked radiator
• Blocked condenser
• Blocked radiator grille
• Blocked bumper• Visual No blocking —
2 • Coolant mixture • Coolant tester 50 - 50% coolant mixtureMA-10
3 • Coolant level • Visual Coolant up to MAX level in
reservoir tank and radiator
filler neckMA-12, "Changing Engine
Coolant"
4 • Reservoir tank cap • Pressure tester 95 - 125 kPa
(0.97 - 1.28 kg/cm2, 14 -
18 psi) (Limit)CO-9, "
Inspection"
ON*25 • Coolant leaks • Visual No leaksCO-9, "Inspection"
ON*26 • Thermostat • Touch the upper and
lower radiator hosesBoth hoses should be hotCO-20
ON*17 • Cooling fan • CONSULT-II Operating See trouble diagnosis for
DTC P1217 (EC-469
).
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 idlingMA-12, "
Changing Engine
Coolant"
OFF*410 • Coolant return from res-
ervoir tank to radiator• Visual Should be initial level in
reservoir tankMA-12, "Changing Engine
Coolant"
OFF 12 • Cylinder head • Straight gauge feeler
gauge0.1 mm (0.004 in) Maxi-
mum distortion (warping)EM-69, "Inspection After
Disassembly"
13 • Cylinder block and pis-
tons• Visual No scuffing on cylinder
walls or pistonEM-93, "Inspection After
Disassembly"
AWBIA0529ZZ

DTC P1225 TP SENSOR
EC-477
< SERVICE INFORMATION >
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DTC P1225 TP SENSOR
Component DescriptionINFOID:0000000003531997
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 Diagnosis LogicINFOID:0000000003531998
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000003531999
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-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. If 1st trip DTC is detected, go to EC-477, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnosis ProcedureINFOID:0000000003532000
1.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
1. Turn ignition switch OFF.
2. Remove the intake air duct.
PBIB0145E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1225
1225Closed throttle position learning
performanceClosed throttle position learning value is
excessively low.• Electric throttle control actuator
(TP sensor 1 and 2)
SEF058Y

EC-478
< SERVICE INFORMATION >
DTC P1225 TP SENSOR
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
1. Replace the electric throttle control actuator.
2. Perform EC-77, "
Throttle Valve Closed Position Learning".
3. Perform EC-78, "
Idle Air Volume Learning".
>>INSPECTION END
Removal and InstallationINFOID:0000000003532001
ELECTRIC THROTTLE CONTROL ACTUATOR
Refer to EM-17.
BBIA0364E

DTC P1226 TP SENSOR
EC-479
< SERVICE INFORMATION >
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DTC P1226 TP SENSOR
Component DescriptionINFOID:0000000003532002
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 Diagnosis LogicINFOID:0000000003532003
The MIL will not light up for this self-diagnosis.
DTC Confirmation ProcedureINFOID:0000000003532004
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-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Repeat steps 3 and 4 for 32 times.
6. If 1st trip DTC is detected, go to EC-479, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnosis ProcedureINFOID:0000000003532005
1.CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
1. Turn ignition switch OFF.
2. Remove the intake air duct.
PBIB0145E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1226
1226Closed throttle position learning
performanceClosed throttle position learning is not performed
successfully, repeatedly.• Electric throttle control actuator
(TP sensor 1 and 2)
SEF058Y

EC-480
< SERVICE INFORMATION >
DTC P1226 TP SENSOR
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
1. Replace the electric throttle control actuator.
2. Perform EC-77, "
Throttle Valve Closed Position Learning".
3. Perform EC-78, "
Idle Air Volume Learning".
>>INSPECTION END
Removal and InstallationINFOID:0000000003532006
ELECTRIC THROTTLE CONTROL ACTUATOR
Refer to EM-17.
BBIA0364E

DTC P1421 COLD START CONTROL
EC-481
< SERVICE INFORMATION >
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DTC P1421 COLD START CONTROL
DescriptionINFOID:0000000003532007
ECM controls ignition timing and engine idle speed when engine is started with prewarming up condition.
This control promotes the activation of three way catalyst by heating the catalyst and reduces emissions.
On Board Diagnosis LogicINFOID:0000000003532008
DTC Confirmation ProcedureINFOID:0000000003532009
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.
•If DTC P1421 is displayed with other DTC, first perform the trouble diagnosis for other DTC.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-II
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-II.
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 the specified value, go
to the following step.
If “COOLANT TEMP/S” indication is out of the specified value,
cool engine down or warm engine up and go to step 1.
5. Start engine and let it idle for 5 minutes.
6. If 1st trip DTC is detected, go to EC-481, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnosis ProcedureINFOID:0000000003532010
1.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-78, "
Idle Air Volume Learning".
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes >> GO TO 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
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1421
1421Cold start emission reduction
strategy monitoringECM 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
SEF174Y