2011 INFINITI QX56 air conditioning

U1024 CAN COMM CIRCUITEC-175
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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U1024 CAN COMM CIRCUIT
DTC LogicINFOID:0000000006217770
DTC DETECTION LOGIC
NOTE:
If DTC U1024 is displayed with DTC P0607, fi
rst perform the trouble diagnosis for DTC P0607.
Refer to EC-378, "
DTC Logic".
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
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 3 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-175, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217771
1.CHECK VVEL CAN COMMUNICATION CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Disconnect VVEL control module harness connector.
4. Check the continuity between ECM harness c onnector and VVEL control module harness connector.
5. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open or short between ECM and VVEL control module
 Loose or poor connection for each connector and harness
>> 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
U1024 VVEL CAN COMM CIRCUIT
(VVEL CAN communication)  When VVEL control module cannot transmitting
or receiving CAN communication signal with
ECM for 2 seconds or more.
 When detecting error during the initial diagnosis
of CAN controller of VVEL control module.  Harness or connectors
(CAN communication line is
open or shorted)
ECM
 VVEL control module
ECM VVEL control module Continuity
Connector Terminal Connector Terminal
E80 161
F56 24
Existed
166 11
Revision: 2010 May2011 QX56

P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER
EC-181
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER
DTC LogicINFOID:0000000006217775
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 let it idle for at least 10 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-181, "Diagnosis Procedure".
NG >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217776
1.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect air fuel ratio (A /F) sensor 1 harness connector.
2. Turn ignition switch ON.
3. Check the voltage between A/F sensor 1 harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
DTC No. Trouble diagnosis
(Trouble diagnosis content) DTC detecting condition Possible cause
P0031 A/F SEN1 HTR (B1)
[A/F sensor 1 heater (bank
1) control circuit low] The current amperage in the A/F sensor 1 heater
circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the A/F sensor 1 heater.)  Harness or connectors
(The A/F sensor 1 heater circuit is
open or shorted.)
 A/F sensor 1 heater
P0032 A/F SEN1 HTR (B1)
[A/F sensor 1 heater (bank
1) control circuit high] The current amperage in the A/F sensor 1 heater
circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the A/F sensor 1 heater.)  Harness or connectors
(The A/F sensor 1 heater circuit is
shorted.)
 A/F sensor 1 heater
P0051 A/F SEN1 HTR (B2)
[A/F sensor 1 heater (bank
2) control circuit low] The current amperage in the A/F sensor 1 heater
circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the A/F sensor 1 heater.)  Harness or connectors
(The A/F sensor 1 heater circuit is
open or shorted.)
 A/F sensor 1 heater
P0052 A/F SEN1 HTR (B2)
[A/F sensor 1 heater (bank
2) control circuit high] The current amperage in the A/F sensor 1 heater
circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the A/F sensor 1 heater.)  Harness or connectors
(The A/F sensor 1 heater circuit is
shorted.)
 A/F sensor 1 heater
DTC A/F sensor 1
Ground Voltage
Bank Connector Terminal
P0031, P0032 1 F67 5 Ground Battery voltage
P0051, P0052 2 F68 5
Revision: 2010 May2011 QX56

P006A, P0101 MAF SENSOREC-187
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P006A, P0101 MAF SENSOR
DTC LogicINFOID:0000000006288269
DTC DETECTION LOGIC
NOTE:
If DTC P006A or P0101 is displayed with other DTC,
first perform the trouble diagnosis for other DTC.
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.
If engine will not start or stops soon, wait at leas t 10 seconds with engine stopped (Ignition switch ON) instead
of running engine at idle speed.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
2. Start engine and warm it up to normal operating temperature.
3. Accelerate the vehicle from 0 km/h (0 MPH) to 88 km/h (55 MPH) under the following conditions:
CAUTION:
Always drive at a safe speed.
NOTE:
 Accelerate with the accelerator pedal kept constant.
 The acceleration at engine speed 2,000 and 3,000 rpm allows easy diagnoses
4. Check 1st trip DTC. WITHOUT CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. With selector lever in D position, accelerate the vehicle from 0 km/h (0 MPH) to 88 km/h (55 MPH) under
the following conditions:
NOTE:
 Accelerate with the accelerator pedal kept constant.
 The acceleration at engine speed 2,000 and 3,000 rpm allows easy diagnoses.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P006A MAP-MAF CORELTION-B1
(Manifold pressure
- mass air
flow correlation) A difference exceeding the specified value develops
between a value transmitted from the manifold absolute
pressure sensor to ECM and an estimated intake pres-
sure of intake manifold calculated by ECM, based on a
mass sir flow sensor signal.  Harness or connectors
(The sensor circuit is open
or shorted.)
 Mass air flow sensor
 Manifold absolute pressure
sensor
 EVAP control system pres-
sure sensor
 Intake air leaks
 Intake air temperature sen- sor
P0101 MAF SEN/CIRCUIT-B1
(Mass air flow sensor circuit
range/performance) A difference exceeding the specified value develops
between a signal transmitted from the mass air flow
sensor to ECM.
Mass air flow sensor
ACCEL SEN 1 1.4 – 2.0 V
Selector lever D position
Revision: 2010 May2011 QX56

P0075, P0081 IVT CONTROL SOLENOID VALVE
EC-193
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0075, P0081 IVT CONTRO
L SOLENOID VALVE
DTC LogicINFOID:0000000006217781
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 5 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-193, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217782
1.CHECK INTAKE VALVE TIMING CONTROL SO LENOID VALVE POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect intake valve timing (IVT) control solenoid valve harness connector.
3. Turn ignition switch ON.
4. Check the voltage between IVT control solenoid valve harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open or short between IVT control solenoid valve and IPDM E/R
 Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
3.CHECK IVT CONTROL SOLENOID VALVE OUTP UT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0075 INT/V TIM V/CIR-B1
[Intake valve timing control sole-
noid valve (bank 1) circuit]
An improper voltage is sent to the ECM
through intake valve timing control solenoid
valve.  Harness or connectors
(Intake valve timing control solenoid
valve circuit is open or shorted.)
 Intake valve timing control solenoid valve
P0081 INT/V TIM V/CIR-B2
[Intake valve timing control sole-
noid valve (bank 2) circuit]
DTC
IVT control solenoid valve
Ground Voltage
Bank Connector Terminal
P0075 1 F47 2 Ground Battery voltage
P0081 2 F61 2
Revision: 2010 May2011 QX56

EC-198
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P008A LOW FUEL PRESSURE CONTROL SYSTEM
P008A LOW FUEL PRESSURE CONTROL SYSTEM
DTC LogicINFOID:0000000006217787
DTC DETECTION LOGIC
NOTE:
If DTC P008A is displayed with DTC P1197, first pe
rform the trouble diagnosis for DTC P1197. Refer to
EC-397, "
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, confirm that battery voltage is 11 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Check that the fuel tank is 1/8 full of fuel.
2. Start the engine and warm it up to the normal operating temperature. NOTE:
When replacing ECM, warm up the engine until “C OOLAN TEMP/S” on “DATA MONITOR” of CONSULT-
III reaches at least 70 °C (158 °F).
3. Let the engine at idle for 60 seconds.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-398, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217788
1.PERFORM LOW PRESSURE FUEL PUMP COMPONENT FUNCTION CHECK
Refer to EC-512, "
Component Function Check".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Perform low pressure fuel pump diagnosis. Refer to EC-512, "
Diagnosis Procedure".
2.CHECK FUEL LEAKAGE
1. Start the engine.
2. Visually check that the low fuel pressure system has no fuel leakage.
Is inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace error-detected parts.
3.CHECK LOW PRESSURE FUEL PIPING AND HOSE
1. Turn ignition switch OFF.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P008A Low fuel pressure too low A condition of low fuel pressure 0.23
MPa (2.3 bar, 2.346 kg/cm
2, 33.35 psi)
or less continues for 5 seconds or more
after warming up the engine.  Harness or connectors
(The low pressure fuel pump circuit is
open or shorted.)
 Low pressure fuel pump
 Fuel pressure regulator
 Low pressure fuel system
 Out of gas
Revision: 2010 May2011 QX56

EC-200
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P008B LOW FUEL PRESSURE CONTROL SYSTEM
P008B LOW FUEL PRESSURE CONTROL SYSTEM
DTC LogicINFOID:0000000006288272
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next test.
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 60 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-200, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288273
1.CHECK FUEL PUMP CONTROL MODULE (FPCM) SIGNAL
Refer to EC-405, "
Component Inspection (FPCM)".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Replace FPCM. Refer to EC-537, "
Removal and Installation".
2.CHECK FUEL PUMP CONTROL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect FPCM harness connector and fuel level sensor unit and fuel pump harness connector.
3. Check the continuity between FPCM harness connecto r and fuel level sensor unit and fuel pump harness
connector.
4. Also check harness for short to ground and short to power.
Is inspection result normal?
YES >> Replace fuel level sensor unit and fuel pump (fuel pressure regulator malfunction). Refer to FL-5,
"Removal and Installation".
NO >> Repair or replace error-detected parts.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P008B Low fuel pressure too high A condition of low fuel pressure 0.67
MPa (6.7 bar, 6.834 kg/cm
2, 97.15 psi)
or more continues for 5 seconds or
more after warming up the engine.  Harness or connectors
(The low pressure fuel pump circuit is
open or shorted.)
 Fuel pressure regulator
FPCM Fuel level sensor unit and fuel pump Continuity
Connector Terminal Connector Terminal
B41 6
C5 3
Existed
71
Revision: 2010 May2011 QX56

P0102, P0103 MAF SENSOREC-201
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P0102, P0103 MAF SENSOR
DTC LogicINFOID:0000000006217789
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
Which DTC is detected?
P0102 >> GO TO 2.
P0103 >> GO TO 3.
2.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0102
1. Start engine and wait at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-201, "Diagnosis Procedure".
NO >> INSPECTION END
3.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0103-I
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-201, "Diagnosis Procedure".
NO >> GO TO 4.
4.PERFORM DTC CONFIRMATION PROCEDURE FOR DTC P0103-II
1. Start engine and wait at least 5 seconds.
2. Check DTC.
Is DTC detected?
YES >> Go to EC-201, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217790
1.INSPECTION START
Confirm the detected DTC.
Which DTC is detected?
P0102 >> GO TO 2.
P0103 >> GO TO 3.
2.CHECK INTAKE SYSTEM
Check the following for connection.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0102 MAF SEN/CIRCUIT-B1
(Mass air flow sensor circuit
low input) An excessively low voltage from the sensor is
sent to ECM.  Harness or connectors
(The mass air flow sensor circuit is
open or shorted.)
 Intake air leakage
 Mass air flow sensor
P0103 MAF SEN/CIRCUIT-B1
(Mass air flow sensor circuit
high input) An excessively high voltage from the sensor is
sent to ECM.  Harness or connectors
(The mass air flow sensor circuit is
open or shorted.)
 Mass air flow sensor
Revision: 2010 May2011 QX56

EC-206
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0106 MANIFOLD ABSOL
UTE PRESSURE SENSOR
P0106 MANIFOLD ABSOLU TE PRESSURE SENSOR
DTC LogicINFOID:0000000006288274
DTC DETECTION LOGIC
NOTE:
If DTC P0106 is displayed with ot her DTC, first perform the trouble diagnosis for other DTC.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next test.
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.
If engine will not start or stops soon, wait at leas t 10 seconds with engine stopped (Ignition switch ON) instead
of running engine at idle speed.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
2. Start engine and warm it up to normal operating temperature.
3. Accelerate the vehicle from 0 to 88 km/h (0 to 55 MPH) under the following conditions: CAUTION:
Always drive at a safe speed.
NOTE:
 Accelerate with the accelerator pedal kept constant.
 The acceleration at engine speed 2,000 and 3,000 rpm allows easy diagnoses.
4. Check 1st trip DTC. WITHOUT CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Drive the vehicle under the following conditions.
3. With selector lever in D position, accelerate the v ehicle from 0 to 88 km/h (0 to 55 MPH) under the follow-
ing conditions:
CAUTION:
Always drive at a safe speed.
NOTE:
 Accelerate with the accelerator pedal kept constant.
 The acceleration at engine speed 2,000 and 3,000 rpm allows easy diagnoses.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P0106 ABSL PRES SEN/CIRC
[Manifold absolute pressure (MAP)
circuit range/performance] A difference exceeding the specified
value develops between a value
transmitted from the manifold abso-
lute pressure (MAP) sensor to ECM
and an estimated intake pressure of
intake manifold calculated by ECM.  Harness or connectors
(The manifold absolute pressure
(MAP) sensor circuit is open or
shorted.)
 manifold absolute pressure (MAP)
sensor
 Intake air leaks
ACCEL SEN 1 1.4 – 2.0 V
Selector lever D position
Revision: 2010 May2011 QX56