2011 INFINITI QX56 check engine

DIAGNOSIS SYSTEM (ECM)EC-71
< SYSTEM DESCRIPTION > [VK56VD]
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*: Leaving cooling fan OFF with CONSULT-III while engine is running may cause the engine to overheat.
DTC & SRT CONFIRMATION MODE
SRT STATUS Mode
For items whose SRT codes are set, “CMPLT” is disp
layed on the CONSULT-III screen; for items whose SRT
codes are not set, “INCMP” is displayed.
SRT WORK SUPPORT Mode
This mode enables a technician to drive a vehicle to set the SRT while monitoring the SRT status.
DTC WORK SUPPORT Mode
*: DTC P1456 does not apply but appears in DTC Work Support Mode screens. V/T ASSIGN AN-
GLE
 Engine: Return to the original
non-standard condition
 Change intake valve timing using CONSULT-III. If malfunctioning symptom disap-
pears, see CHECK ITEM.
 Harness and connectors
 Intake valve timing control sole-
noid valve
FPCM  Engine: Return to the original
trouble condition
 Select “LOW”, “MID” and “HI” with CONSULT-III. Fuel pump speed changes or stops.
 Harness and connectors
 Fuel pump control module (FPCM)
TEST ITEM CONDITION JUDGMENT CHECK ITEM (REMEDY)
Test mode Test item Corresponding DTC No. Reference page
HO2S2 HO2S2 (B1) P1146 P0138
EC-249
HO2S2 (B1) P1147 P0137EC-243
HO2S2 (B1) P0139 P0139EC-257
HO2S2 (B2) P1166 P0158EC-249
HO2S2 (B2) P1167 P0157EC-243
HO2S2 (B2) P0159 P0159EC-257
A/F SEN1A/F SEN1 (B1) P1278/P1279 P0133
EC-238A/F SEN1 (B1) P1276 P0130EC-228
A/F SEN1 (B2) P1288/P1289 P0153EC-238
A/F SEN1 (B2) P1286 P0150EC-228
EVAPORATIVE SYSTEMEVP V/S LEAK P0456/P1456* P0456
EC-346, "
DTC Logic"
PURG VOL CN/V P1444 P0443EC-317, "DTC Logic"
PURG FLOW P0441 P0441EC-312, "DTC Logic"
Revision: 2010 May2011 QX56

EC-92
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
142
(R/W) 175
(B) Fuel pump control module
(FPCM) check
Input[When cranking engine] 0 V
[Engine is running]
 Warm-up condition
 Idle speed
9 V
143
(L/Y) 150
(R) EVAP control system pressure
sensor
Input [Ignition switch: ON] 1.8 - 4.8 V
144
(O/B) 150
(R) Refrigerant pressure sensor Input [Engine is running]
 Warm-up condition
 Both A/C switch and blower fan mo-
tor switch: ON (Compressor oper-
ates) 1.0 - 4.0 V
146 (L) — CAN communication line — — —
147
(G/Y) 175
(B) ASCD/ICC brake switch Input [Ignition switch: ON]
 Brake pedal: Slightly depressed
0 V
[Ignition switch: ON]
 Brake pedal: Fully released BATTERY VOLTAGE
(11 - 14 V)
150 (R) —Sensor ground
(Refrigerant pressure sensor/
Battery current sensor/EVAP
control system pressure sensor) —— —
151 (P) — CAN communication line — — —
156 (L) 175
(B) Power supply
for ECM (Back-
up) Input [Ignition switch: OFF] BATTERY VOLTAGE
(11 - 14 V)
158
(W/B) 175
(B) Stop lamp switch Input [Ignition switch: OFF]
 Brake pedal: Fully released
0 V
[Ignition switch: OFF]
 Brake pedal: Slightly depressed BATTERY VOLTAGE
(11 - 14 V)
161 (R/W) — ENG communication line — — —
163
(L/G) 175
(B) ECM relay (Self shut-off) Output [Engine is running]
[Ignition switch: OFF]
 A few seconds after turning ignition
switch OFF 0 - 1.5 V
[Ignition switch: OFF]
 More than a few seconds after turn- ing ignition switch OFF BATTERY VOLTAGE
(11 - 14 V)
165
(GR/ R) —
NOTE:
Not used —— —
166 (W) — ENG communication line — — —
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
Revision: 2010 May2011 QX56

EC-110
< ECU DIAGNOSIS INFORMATION >[VK56VD]
VVEL CONTROL MODULE
VVEL CONTROL MODULE
Reference ValueINFOID:0000000006217735
TERMINAL LAYOUT
PHYSICAL VALUES
NOTE:
 VVEL control module is located under the battery. Temporarily remove the battery to check voltage of the
terminals.
 Specification data are reference values and are measured between each terminals.
 Pulse signal is measured by CONSULT-III.
JMBIA0857ZZ
Terminal No. Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
1
(R) 14
(B) VVEL actuator motor power
supply (bank 2)
Input [Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)
2
(L/W) 14
(B) VVEL actuator motor
(High lift) (bank 2)
Output[Engine is running]
 Warm-up condition
 Idle speed
0 - 14 V
[Engine is running]
 Warm-up condition
 When revving engine up to 2,000 rpm quickly 0 - 14 V
3
(W) 6
(R) VVEL control shaft position
sensor 1 (bank 1)
Input[Engine is running]
 Warm-up condition
 Idle speed
0.25 - 1.40 V
[Engine is running]
 Warm-up condition
 When revving engine up to 3,000 rpm quickly 0.25 - 4.75 V
4
(L/W) —Sensor ground
[VVEL control shaft position
sensor 1 (bank 2)] —— —
JMBIA0854ZZ
JMBIA0855ZZ
Revision: 2010 May2011 QX56

BASIC INSPECTIONEC-139
< BASIC INSPECTION > [VK56VD]
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BASIC INSPECTION
Work ProcedureINFOID:0000000006217739
1.INSPECTION START
1. Check service records for any recent repairs that ma y indicate a related malfunction, or a current need for
scheduled maintenance.
2. Open engine hood and check the following:
- Harness connectors for improper connections
- Wiring harness for improper connections, pinches and cut
- Vacuum hoses for splits, kinks and improper connections
- Hoses and ducts for leakage
- Air cleaner clogging
- Gasket
3. Check that electrical or mechanical loads are not applied.
- Headlamp switch is OFF.
- Air conditioner switch is OFF.
- Rear window defogger switch is OFF.
- Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature indicator points to the middle of gauge.
Check that engine stays below 1,000 rpm.
5. Run engine at approximately 2,000 rpm for approximately 2 min- utes under no load.
6. Check that no DTC is displayed with CONSULT-III or GST.
Are any DTCs detected?
YES >> GO TO 2.
NO >> GO TO 3.
2.REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding Diagnosis Procedure.
>> GO TO 3
3.CHECK IDLE SPEED
1. Run engine at approximately 2,000 rpm for approximately 2 minutes under no load.
SEF983U
SEF976U
SEF977U
Revision: 2010 May2011 QX56

EC-140
< BASIC INSPECTION >[VK56VD]
BASIC INSPECTION
2. Rev engine between 2,000 and 3,000 rpm 2 or 3 times under no
load, then run engine at idle speed for approximately 1 minute.
3. Check idle speed.
For procedure, refer to EC-530, "
Inspection".
For specification, refer to EC-538, "
Idle Speed".
Is the inspection result normal?
YES >> GO TO 10.
NO >> GO TO 4.
4.PERFORM ACCELERATOR PEDAL RE LEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-146, "
Work Procedure".
>> GO TO 5.
5.PERFORM THROTTLE VALVE CL OSED POSITION LEARNING
Perform EC-147, "
Work Procedure".
>> GO TO 6.
6.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-148, "
Work Procedure".
Is Idle Air Volume Learning carried out successfully?
YES >> GO TO 7.
NO >> Follow the instruction of Idle Air Volume Learning. Then GO TO 4.
7.CHECK IDLE SPEED AGAIN
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. For procedure, refer to EC-530, "
Inspection".
For specification, refer to EC-538, "
Idle Speed".
Is the inspection result normal?
YES >> GO TO 10.
NO >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the Following.
 Check camshaft position sensor and circuit. Refer to EC-303, "
DTC Logic".
 Check crankshaft position sensor and circuit. Refer to EC-299, "
DTC Logic".
Is the inspection result normal?
YES >> GO TO 9.
NO >> Repair or replace malfunctioning part. Then GO TO 4.
9.CHECK ECM FUNCTION
1. Substitute with a non-malfunctioning ECM to check EC M function. (ECM may be the cause of the incident,
although this is rare.)
2. Perform initialization of IVIS (NATS) system and regist ration of all IVIS (NATS) ignition key IDs. Refer to
SEC-51, "
ECM : Work Procedure".
>> GO TO 4.
10.CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light. For procedure, refer to EC-531, "
Inspection".
PBIA8513J
Revision: 2010 May2011 QX56

BASIC INSPECTIONEC-141
< BASIC INSPECTION > [VK56VD]
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For specification, refer to
EC-538, "Ignition Timing".
Is the inspection result normal?
YES >> GO TO 19.
NO >> GO TO 11.
11 .PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-146, "
Work Procedure".
>> GO TO 12.
12.PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-147, "
Work Procedure".
>> GO TO 13.
13.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-148, "
Work Procedure".
Is Idle Air Volume Learning carried out successfully?
YES >> GO TO 14.
NO >> Follow the instruction of Idle Air Volume Learning. Then GO TO 4.
14.CHECK IDLE SPEED AGAIN
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. For procedure, refer to EC-530, "
Inspection".
For specification, refer to EC-538, "
Idle Speed".
Is the inspection result normal?
YES >> GO TO 15.
NO >> GO TO 17.
15.CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light. For procedure, refer to EC-531, "
Inspection".
For specification, refer to EC-538, "
Ignition Timing".
Is the inspection result normal?
YES >> GO TO 19.
NO >> GO TO 16.
16.CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-62, "
Removal and Installation".
Is the inspection result normal?
YES >> GO TO 17.
NO >> Repair the timing chain installation. Then GO TO 4.
17.DETECT MALFUNCTIONING PART
Check the following.
 Check camshaft position sensor and circuit. Refer to EC-303, "
DTC Logic".
 Check crankshaft position sensor and circuit. Refer to EC-299, "
DTC Logic".
Is the inspection result normal?
YES >> GO TO 18.
NO >> Repair or replace malfunctioning part. Then GO TO 4.
18.CHECK ECM FUNCTION
1. Substitute with a non-malfunctioning ECM to check EC M function. (ECM may be the cause of the incident,
although this is rare.)
Revision: 2010 May2011 QX56

VIN REGISTRATIONEC-145
< BASIC INSPECTION > [VK56VD]
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VIN REGISTRATION
DescriptionINFOID:0000000006217744
VIN Registration is an operation to register VIN in
ECM. It must be performed each time ECM is replaced.
NOTE:
Accurate VIN which is registered in ECM may be required for Inspection & Maintenance (I/M).
Work ProcedureINFOID:0000000006217745
1.CHECK VIN
Check the VIN of the vehicle and note it. Refer to GI-23, "
Information About Identification or Model Code".
>> GO TO 2.
2.PERFORM VIN REGISTRATION
WITH CONSULT-III
1. Turn ignition switch ON with engine stopped.
2. Select “VIN REGISTRATION” in “WORK SUPPORT” mode.
3. Follow the instructions on the CONSULT-III display.
>> END
Revision: 2010 May2011 QX56

THROTTLE VALVE CLOSED POSITION LEARNINGEC-147
< BASIC INSPECTION > [VK56VD]
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THROTTLE VALVE CLOSED
POSITION LEARNING
DescriptionINFOID:0000000006217748
Throttle Valve Closed Position Learning is a function of ECM to learn the fully closed position of the throttle
valve by monitoring the throttle position sensor output signal. It must be performed each time the harness con-
nector of the electric throttle control actuator or ECM is disconnected or elec tric throttle control actuator inside
is cleaned.
Work ProcedureINFOID:0000000006217749
1.START
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “CLSD THL POS LEARN” in “WORK SUPPORT” mode.
3. Follow the instructions on the CONSULT-III display.
4. Turn ignition switch OFF and wait at least 10 seconds.
Check that throttle valve moves during the above 10 seconds by confirming the operating sound.
WITHOUT CONSULT-III
1. Start the engine.
NOTE:
Engine coolant temperature is 25 °C (77 °F) or less before engine starts.
2. Warm up the engine. NOTE:
Raise engine coolant temperature until it reaches 65 °C (149 °F) or more.
3. Turn ignition switch OFF and wait at least 10 seconds. Check that throttle valve moves during the above 10 seconds by confirming the operating sound.
>> END
Revision: 2010 May2011 QX56