2011 INFINITI QX56 display

EC-408
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1421 COLD START CONTROL
P1421 COLD START CONTROL
DescriptionINFOID:0000000006288263
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.
DTC LogicINFOID:0000000006288264
DTC DETECTION LOGIC
NOTE:
If DTC P1421 is displayed with other DTC, firs t 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.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11 V at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Check the indication of “COOLAN TEMP/S”. If it is between 7 °C (45 °F) and 36 °C (97 °F), go to the following steps.
If it is below 7 °C (45 °F), warm engine up to more than 7 °C (45 °F) and retry from step 1.
If it is above 36 °C (97 °F), cool engine down to less than 36 °C (97 °F) and retry from step 1.
5. Start engine and let it idle for 5 minutes.
6. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-408, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288265
1.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-148, "
Work Procedure".
Is Idle Air Volume Learning carried out successfully?
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
Is the inspection result normal?
YES >> GO TO 3.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1421 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: 2010 May2011 QX56

P1421 COLD START CONTROLEC-409
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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NO >> Repair or replace malfunctioning part
3.CHECK FUEL INJECTION SYSTEM FUNCTION
Perform DTC Confirmation Procedure for DTC P0171, P0174. Refer to EC-263, "
DTC Logic".
Is the inspection result normal?
YES >> GO TO 4.
NO >> Go to EC-264, "
Diagnosis Procedure" for DTC P0171, P0174.
4.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Erase DTC.
3. Perform DTC Confirmation Procedure.
See EC-408, "
DTC Logic".
Is the 1st trip DTC P1421 displayed again?
YES >> GO TO 5.
NO >> INSPECTION END
5.REPLACE ECM
1. Replace ECM.
2. Go to EC-143, "
Work Procedure".
>> INSPECTION END
Revision: 2010 May2011 QX56

EC-410
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1423, P1424 COLD
START CONTROL
P1423, P1424 COLD START CONTROL
DescriptionINFOID:0000000006288266
ECM controls fuel injection timing and fuel injection quantity when engine is started with the engine cold.
This control promotes the activation of three way ca talyst by heating the catalyst and reduces emissions.
DTC LogicINFOID:0000000006288267
DTC DETECTION LOGIC
NOTE:
If DTC P1423 or P1424 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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
WITH CONSULT-III
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Check that “COOLAN TEMP/S”.
- If it is between 5 °C (41 °F) and 40 °C (104 °F) go to the following steps.
- If it is below 5 °C (41 °F) warm engine up to more than 5 °C (41 °F) and retry from step 1.
- If it is above 40 °C (104 °F) cool engine down to less than 40 °C (104 °F) and retry from step 1.
5. Start engine and let it idle for 5 minutes.
6. Check 1st trip DTC.
WITH GST
Follow the procedure “With CONSULT-III” above.
Is 1st trip DTC detected?
YES >> Proceed to EC-410, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288268
1.INSPECTION START
1. Turn ignition switch ON.
2. Erase DTC.
3. Perform DTC confirmation procedure. Refer to EC-410, "
DTC Logic".
4. Check 1st trip DTC.
Is the 1st trip DTC P1423 or P1424 displayed again?
YES >> GO TO 2.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1423 COLD START CONTROL
(Cold start emission reduction
strategy monitoring) ECM does not control fuel injection timing prop-
erly when engine is started with the engine cold.
ECM
P1424 COLD START CONTROL
(Cold start emission reduction
strategy monitoring) ECM does not control fuel injection quantity
properly when engine is started with with the en-
gine cold.
Revision: 2010 May2011 QX56

EC-428
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1556, P1557 BATTERY
TEMPERATURE SENSOR
P1556, P1557 BATTERY TEMPERATURE SENSOR
DTC LogicINFOID:0000000006217932
DTC DETECTION LOGIC
NOTE:
If DTC P1556 or P1557 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.
Refer to EC-381, "
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 the engine and let it idle at least 10 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-428, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217933
1.CHECK BATTERY TEMPERATURE SENSOR INPUT SIGNAL CIRCUIT-I
1. Disconnect battery current sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between battery current sensor hrness connector and ground.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 2.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1556 BAT TMP SEN/CIRC
(Battery temperature sensor
circuit low input) Signal voltage from Battery
temperature sensor remains
0.16V or less for 5 seconds
or more. Harness or connectors
[Battery current sensor (Battery temperature sensor)
circuit is shorted.]
(Crankshaft position sensor circuit is open or shorted.)
[Camshaft position sensor (bank 1) circuit is shorted.]
(Accelerator pedal position sensor 2 circuit is shorted.)
(Refrigerant pressure sensor circuit is shorted.)
(EVAP control system pressure sensor circuit is short-
ed.)
 Battery current sensor (Battery temperature sensor)
 Crankshaft position sensor
 Camshaft position sensor (bank 1)
 Accelerator pedal position sensor 2
 Refrigerant pressure sensor
 EVAP control system pressure sensor
P1557
BAT TMP SEN/CIRC
(Battery temperature sensor
circuit high input) Signal voltage from Battery
temperature sensor remains
4.84V or more for 5 seconds
or more.
Battery current sensor
Ground Voltage (V)
Connector Terminal
E63 1 Ground Approx. 5
Revision: 2010 May2011 QX56

P1564 ASCD STEERING SWITCHEC-431
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P1564 ASCD STEERING SWITCH
DTC LogicINFOID:0000000006217935
DTC DETECTION LOGIC
NOTE:
If DTC P1564 is displayed with DTC P0605, first pe
rform the trouble diagnosis for DTC P0605. Refer to
EC-376, "
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON and wait at least 10 seconds.
2. Press MAIN switch for at least 10 seconds, then release it and wait at least 10 seconds.
3. Press CANCEL switch for at least 10 seconds, then release it and wait at least 10 seconds.
4. Press RESUME/ACCELERATE switch for at least 10 seconds, then release it and wait at least 10 sec-
onds.
5. Press SET/COAST switch for at least 10 seconds , then release it and wait at least 10 seconds.
6. Check DTC.
Is DTC detected?
YES >> Go to EC-431, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217936
1.CHECK ASCD STEERING SWITCH CIRCUIT
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “MAIN SW”, “CANCEL SW”, “RESUME/ACC SW” and “SET SW” in “DATA MONITOR” mode with
CONSULT-III.
3. Check each item indication under the following conditions.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1564 ASCD SW
(ASCD steering switch)  An excessively high voltage signal from the
ASCD steering switch is sent to ECM.
 ECM detects that input signal from the ASCD steering switch is out of the specified
range.
 ECM detects that the ASCD steering switch is stuck ON.  Harness or connectors
(The switch circuit is open or shorted.)
 ASCD steering switch
ECM
Monitor item Condition Indication
MAIN SW MAIN switch Pressed ON
Released OFF
CANCEL SW CANCEL switch Pressed ON
Released OFF
RESUME/ACC SW RESUME/ACCELERATE
switch Pressed ON
Released OFF
Revision: 2010 May2011 QX56

EC-434
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1564 ICC STEERING SWITCH
P1564 ICC STEERING SWITCH
DTC LogicINFOID:0000000006217938
DTC DETECTION LOGIC
NOTE:
If DTC P1564 is displayed with DTC P0605, first pe
rform the trouble diagnosis for DTC P0605. Refer to
EC-376, "
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.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON and wait at least 10 seconds.
2. Press MAIN switch for at least 10 seconds, then release it and wait at least 10 seconds.
3. Press CANCEL switch for at least 10 seconds , then release it and wait at least 10 seconds.
4. Press RESUME/ACCELERATE switch for at least 10 seconds, then release it and wait at least 10 sec-
onds.
5. Press SET/COAST switch for at least 10 seconds , then release it and wait at least 10 seconds.
6. Press DISTANCE switch for at least 10 seconds , then release it and wait at least 10 seconds.
7. Press LDP switch for at least 10 seconds, t hen release it at wait at least 10 seconds.
8. Check DTC.
Is DTC detected?
YES >> Go to EC-434, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217939
1.CHECK ICC STEERING SWITCH CIRCUIT
1. Turn ignition switch ON.
2. Check the voltage between ECM harness connector terminals under the following conditions.
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1564 ASCD SW
(ICC steering switch)  An excessively high voltage signal from the
ICC steering switch is sent to ECM.
 ECM detects that input signal from the ICC steering switch is out of the specified range.
 ECM detects that the ICC steering switch is stuck ON.  Harness or connectors
(The switch circuit is open or shorted.)
 ICC steering switch
ECM
Revision: 2010 May2011 QX56

P1568 ICC FUNCTIONEC-437
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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P1568 ICC FUNCTION
DTC LogicINFOID:0000000006217941
DTC DETECTION LOGIC
NOTE:

If DTC P1568 is displayed with DTC UXXXX, perform the trouble diagnosis for DTC UXXXX.
 If DTC P1568 is displayed with DTC P0605, perform the trouble diagnosis for DTC P0605. Refer to
EC-376, "
DTC Logic".
 If DTC P1568 is displayed with DTC P0607, perform the trouble diagnosis for DTC P0607. Refer to
EC-378, "
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:
Step 2 may be conducted with the dr ive wheels lifted in the shop or by driving the vehicle. If a road test
is expected to be easier, it is unnecessary to lift the vehicle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Press MAIN switch on ICC steering switch.
3. Drive the vehicle at more than 40 km/h (25 MPH). CAUTION:
Always drive vehicle at a safe speed.
4. Press SET/COAST switch.
5. Check DTC.
Is DTC detected?
YES >> Go to EC-437, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217942
1.REPLACE ADAS CONTROL UNIT
1. Replace ADAS control unit. Refer to DAS-63, "
Removal and Installation".
2. Check DTC of ADAS control unit. Refer to DAS-38, "
DTC Index".
>> INSPECTION END
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC Detecting Condit
ion Possible Cause
P1568 ICC COMMAND VALUE
(ICC function) ECM detects a difference between signals
from ADAS control unit is out of specified
range.  Harness or connectors
(The CAN communication line is open or
shorted.)
 ADAS control unit
ECM
Revision: 2010 May2011 QX56

EC-438
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1572 ASCD BRAKE SWITCH
P1572 ASCD BRAKE SWITCH
DTC LogicINFOID:0000000006217943
DTC DETECTION LOGIC
NOTE:

If DTC P1572 is displayed with DTC P0605, first pe rform the trouble diagnosis for DTC P0605. Refer
to EC-376, "
DTC Logic".
 This self-diagnosis has the one tr ip detection logic. When malfunction A is detected, DTC is not
stored in ECM memory. And in that case, 1st trip DTC and 1st trip freeze frame data are displayed.
1st trip DTC is erased when ignition switch is tu rned OFF. And even when malfunction A is detected
in two consecutive trips, DTC is not stored in ECM memory.
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.
NOTE:
The procedure for malfunction B is not described. It ta kes an extremely long time to complete the procedure
for malfunction B. By performing the procedure for malfunc tion A, the condition that causes malfunction B can
be detected.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A
1. Start engine (VDC switch OFF).
2. Press MAIN switch and check that CRUISE indicator is displayed in combination meter.
3. Drive the vehicle for at least 5 consec utive seconds under the following conditions.
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheel s lifted in the shop or by driving the vehicle.
If a road test is expected to be easier , it is unnecessary to lift the vehicle.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-439, "Diagnosis Procedure".
NO >> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE
1. Drive the vehicle for at least 5 consec utive seconds under the following conditions.
CAUTION:
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1572 ASCD BRAKE SW
(ASCD brake switch) A)
When the vehicle speed is above 30 km/h
(19 MPH), ON signals from the stop lamp
switch and the ASCD brake switch are
sent to the ECM at the same time.  Harness or connectors
(The stop lamp switch circuit is shorted.)
 Harness or connectors
(The ASCD brake switch circuit is short-
ed.)
 Stop lamp switch
 ASCD brake switch
 Incorrect stop lamp switch installation
 Incorrect ASCD brake switch installation
ECM
B)
ASCD brake switch signal is not sent to
ECM for extremely long time while the ve-
hicle is being driven.
Vehicle speed More than 30 km/h (19 mph)
Selector lever Suitable position
Revision: 2010 May2011 QX56