2011 INFINITI QX56 Fuel

DIAGNOSIS AND REPAIR WORKFLOWEC-137
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Will CONSULT-III be used?
YES >> GO TO 7.
NO >> GO TO 9.
7.PERFORM SPEC IN DATA MONITOR MODE
WITH CONSULT-III
Check that “MAS A/F SE-B1 ”, “B/FUEL SCHDL”, “A/F ALPHA-B1” and “A/F ALPHA-B2” are within the SP
value using “SPEC” in “DATA MONITOR” mode with CONSULT-III. Refer to EC-161, "
Component Function
Check".
Is the measurement value within the SP value?
YES >> GO TO 9.
NO >> GO TO 8.
8.DETECT MALFUNCTIONING PART BY TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Detect malfunctioning part according to EC-162, "
Diagnosis Procedure".
Is a malfunctioning part detected?
YES >> GO TO 11.
NO >> GO TO 9.
9.DETECT MALFUNCTIONING SY STEM BY SYMPTOM TABLE
Detect malfunctioning system according to EC-524, "
Symptom Table" based on the confirmed symptom in
step 4, and determine the trouble diagnosis or der based on possible causes and symptoms.
>> GO TO 10.
10.DETECT MALFUNCTIONING PART BY DIAGNOSIS PROCEDURE
Inspect according to Diagnosis Procedure of the system.
NOTE:
The Diagnosis Procedure in EC section described based on open circuit inspection. A short circuit inspection
is also required for the circuit check in the Diagnosis Procedure. For details, refer to GI-43, "
Circuit Inspec-
tion".
Is a malfunctioning part detected?
YES >> GO TO 11.
NO >> Monitor input data from related sensors or check voltage of related ECM terminals using CON-
SULT-III. Refer to EC-72, "
Reference Value".
11 .REPAIR OR REPLACE THE MALFUNCTIONING PART
1. Repair or replace the malfunctioning part.
2. Reconnect parts or connectors disconnected during Diagnosis Procedure again after repair and replace-
ment.
3. Check DTC. If DTC is displayed, erase it. Re fer to “How to Erase DTC and 1st Trip DTC” in EC-63,
"CONSULT-III Function" or EC-60, "On Board Diagnosis Function".
>> GO TO 12.
12.FINAL CHECK
When DTC was detected in step 2, perform DTC CONFIRMATION PROCEDURE or Component Function
Check again, and then check that the malfunction have been completely repaired.
When symptom was described from the customer, refer to confirmed symptom in step 3 or 4, and check that
the symptom is not detected.
Is DTC detected and does symptom remain?
YES-1 >> DTC is detected: GO TO 10.
YES-2 >> Symptom remains: GO TO 6.
NO >> Before returning the vehicle to the custom er, always erase unnecessary DTC in ECM and TCM
(Transmission Control Module). (Refer to “How to Erase DTC and 1st Trip DTC” in EC-63,
"CONSULT-III Function" or EC-60, "On Board Diagnosis Function".) If the completion of SRT is
Revision: 2010 May2011 QX56

EC-138
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DIAGNOSIS AND REPAIR WORKFLOW
needed, drive vehicle under the specific driving pattern. Refer to
EC-157, "SRT Set Driving Pat-
tern".
Diagnostic Work SheetINFOID:0000000006217738
DESCRIPTION
There are many operating conditions that lead to the malfunction of
engine components. A good grasp of such conditions can make trou-
bleshooting faster and more accurate.
In general, each customer feels differently about symptoms. It is
important to fully understand the symptoms or conditions for a cus-
tomer complaint.
Utilize a diagnostic worksheet like the WORKSHEET SAMPLE
below in order to organize all the information for troubleshooting.
Some conditions may cause the MIL to illuminate or blink, and DTC
to be detected. Examples:
 Vehicle ran out of fuel, which caused the engine to misfire.
 Fuel filler cap was left off or incorrectly screwed on, allowing fuel to
evaporate into the atmosphere.
WORKSHEET SAMPLE
SEF907L
MTBL0017
Revision: 2010 May2011 QX56

FUEL PRESSUREEC-153
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FUEL PRESSURE
Work ProcedureINFOID:0000000006217756
FUEL PRESSURE RELEASE
WITH CONSULT-III
1. Turn ignition switch ON.
2. Perform “FUEL PRESSURE RELEASE” in
“WORK SUPPORT” mode with CONSULT-III.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel pressure.
5. Turn ignition switch OFF.
WITHOUT CONSULT-III
1. Remove fuel pump fuse in IPDM E/R. NOTE:
 For the fuse number, refer to EC-114, "
Wiring Diagram".
 For the fuse arrangement, refer to PG-143, "
Fuse, Connector and Terminal Arrangement".
2. Start engine.
3. After engine stalls, crank it two or three times to release all fuel pressure.
4. Turn ignition switch OFF.
5. Reinstall fuel pump fuse after servicing fuel system.
LOW FUEL PRESSURE CHECK
CAUTION:
 Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.
 The fuel hose connection method used when taking fuel pressure check must not be used for other
purposes.
 Do not perform fuel pressure check with electrical syst ems operating (i.e. lights, rear defogger, A/C,
etc.) Fuel pressure gauge may indicate false readin gs due to varying engine load and changes in
manifold vacuum.
NOTE:
Prepare pans or saucers under the disconnected fuel line because the fuel may spill out.
1. Release fuel pressure to zero.
2. Prepare fuel hose for fuel pressure check (B) and fuel tube adapter [SST (KV10118400)] (D), then connect fuel pressure
gauge (A).
CAUTION:
 Use suitable fuel hose for fuel pressure check (genuine
NISSAN fuel hose without quick connector).
 To avoid unnecessary force or tension to hose, use mod-
erately long fuel hose for fuel pressure check.
 Do not use the fuel hose for checking fuel pressure with damage or cracks on it.
 Use Pressure Gauge to check fuel pressure.
3. Disconnect fuel feed hose from fuel tube. Refer to EM-43, "
Exploded View".
CAUTION:
Do not twist or kink fuel hose because it is plastic hose.
To quick connector
To fuel tube (engine side)
C : Hose clamp
PBIB2982E
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EC-154
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FUEL PRESSURE
4. Connect fuel hose for fuel pressure check (1) to fuel tube
(engine side) with clamp (2) as shown in the figure.
CAUTION:
 Wipe off oil or dirt from hose insertion part using clothmoistened with gasoline.
 Apply proper amount of gasoli ne between top of the fuel
tube (3) and No.1 spool (4).
 Insert fuel hose for fuel pressure check until it touches the No.1 spool on fuel tube.
 Use NISSAN genuine hose clamp (part number: 16439
N4710 or 16439 40U00).
 When reconnecting fuel line, always use new clamps.
 Use a torque driver to tighten clamps.
 Install hose clamp to the position within 1 - 2 mm (0.04 - 0.08 in).
 Make sure that clamp screw does not contact adjacent parts.
5. Connect fuel tube adapter (C) to fuel feed hose (1) in the same manner as instructed in Step 4.
6. After connecting fuel hose for fuel pressure check, pull the hose with a force of approximately 98 N (10 kg,
22 lb) to confirm fuel tube does not come off.
7. Reinstall the part removed at Step 3. NOTE:
Install the part to allow smooth engine starts.
8. Turn ignition switch ON and check for fuel leakage.
9. Start engine and check for fuel leakage.
10. Read the indication of fuel pressure gauge. CAUTION:
 Do not perform fuel pressure check with system operating. Fuel pressure gauge may indicate
false readings.
 During fuel pressure check, confirm for fuel leakage from fuel connection every 3 minutes.
HIGH FUEL PRESSURE CHECK
NOTE:
Since the fuel pressure gauge kit cannot be connected, follow the method shown below to check high fuel
pressure.
WITH CONSULT-III
1. Start engine.
2. Check “FUEL PRES SEN V” in “DATA MONITOR” mode with CONSULT-III.
5 : No.2 spool
Tightening torque : 1.0 - 1.5 N·m (0.1 - 0.15 kg-m, 9 - 13 in-
lb)
A : Fuel pressure gauge
B : Fuel hose for fuel pressure check
PBIB2983E
JSBIA0491ZZ
At idling: Approximately 450 kPa (4.5 bar, 4.6 kg/cm2,
65 psi)
Revision: 2010 May2011 QX56

FUEL PRESSUREEC-155
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OWITHOUT CONSULT-III
1. Start the engine.
2. Check fuel rail pressure sensor signal voltage.
Monitor Item Condition Values/Status
FUEL PRES SEN V Idle 980 – 1,200 mV
Revving engine from idle to 4,000 rpm quickly 1,100 – 2,900 mV
+ − Condition Va l u e
(Approx.)
Fuel rail pressure sensor
Connector Terminal
F26 2 Ground Engine speed: idle 0.98 – 1.2 V
Engine speed: Revving engine from idle to 4,000 rpm quickly 1.1 – 2.9 V
Revision: 2010 May2011 QX56

EC-156
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HOW TO SET SRT CODE
HOW TO SET SRT CODE
DescriptionINFOID:0000000006265593
OUTLINE
In order to set all SRTs, the self-diagnoses as in
the “SRT ITEM” table must have been performed at least
once. Each diagnosis may require actual driving for a long period of time under various conditions.
SRT ITEM
The table below shows required self-diagnostic items to set the SRT to “CMPLT”.
*1: Though displayed on the CONSULT-III screen, “HO2S HTR” is not SRT item.
SRT SERVICE PROCEDURE
If a vehicle has failed the state emissions inspection due to one or more SRT items indicating “INCMP”, review
the flowchart diagnostic sequence, refe rring to the following flowchart.
SRT item*1
(CONSULT-III indication)Required self-diagnostic items to set the SRT to “CMPLT” Corresponding DTC No.
CATALYST Three way catalyst function P0420, P0430
EVAP SYSTEM EVAP control system purge flow monitoring P0441
EVAP control system P0456
HO2S Air fuel ratio (A/F) sensor 1 P0130, P0133, P0150, P0153 Heated oxygen sensor 2 P0137, P0157
Heated oxygen sensor 2 P0138, P0158
Heated oxygen sensor 2 P0139, P0159
EGR/VVT SYSTEM Intake value timing control function P0011, P0021
Revision: 2010 May2011 QX56

HOW TO SET SRT CODEEC-159
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 Flat road
 Ambient air temperature: 20 - 30
°C (68 - 86 °F)
 Diagnosis is performed as quickly as possible under normal conditions.
Under different conditions [For example: ambient air temperature other than 20 - 30 °C (68 - 86 °F)], diagno-
sis may also be performed.
Work ProcedureINFOID:0000000006265595
1.CHECK DTC
Check DTC.
Is any DTC detected?
YES >> Repair malfunction(s) and erase DTC. Refer to EC-98, "DTC Index".
NO >> GO TO 2.
2.CHECK SRT STATUS
WITH CONSULT-III
Select “SRT STATUS” in “DTC & SRT CONFIRMATION” mode with CONSULT-III.
WITHOUT CONSULT-III
Perform “SRT status” mode with EC-60, "
On Board Diagnosis Function".
WITH GST
Select Service $01 with GST.
Is SRT code(s) set?
YES >> END
NO-1 >> With CONSULT-III: GO TO 3.
NO-2 >> Without CONSULT-III: GO TO 4.
3.DTC CONFIRMATION PROCEDURE
1. Select “SRT WORK SUPPORT” in “DTC & SRT CONFIRMATION” mode with CONSULT-III.
2. For SRT(s) that is not set, perform the corre sponding “DTC CONFIRMATION PROCEDURE” according to
the “Performance Priority” in t he “SRT ITEM” table. Refer to EC-156, "
Description".
3. Check DTC.
Is any DTC detected?
YES >> Repair malfunction(s) and erase DTC. Refer to EC-98, "DTC Index".
NO >> GO TO 10.
4.PERFORM ROAD TEST
 Check the “Performance Priority” in the “SRT ITEM” table. Refer to EC-156, "
Description".
 Perform the most efficient SRT set drivi ng pattern to set the SRT properly. Refer to EC-157, "
SRT Set Driv-
ing Pattern".
In order to set all SRTs, the SRT set driving pattern must be performed at least once.
>> GO TO 5.
5.PATTERN 1
1. Check the vehicle condition;
- Engine coolant temperature is −10 to 35 °C (14 to 95 °F).
- Fuel tank temperature is more than 0 °C (32 °F).
2. Start the engine.
3. Keep engine idling until the engine coolant temperature is greater than 70 °C (158 °F)
NOTE:
ECM terminal voltage is follows;
 Engine coolant temperature
- −10 to 35 °C (14 to 95 °F): 3.0 - 4.3 V
-70 °(158 °F): Less than 1.4 V
 Fuel tank temperature: Less than 4.1 V
Refer to EC-72, "
Reference Value".
>> GO TO 6.
Revision: 2010 May2011 QX56

TROUBLE DIAGNOSIS - SPECIFICATION VALUEEC-161
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DTC/CIRCUIT DIAGNOSIS
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
DescriptionINFOID:0000000006217760
The specification (SP) value indicates the tolerance of
the value that is displayed in “SPEC” in “DATA MONI-
TOR” mode of CONSULT-III during normal operation of the Engine Control System. When the value in “SPEC”
in “DATA MONITOR” mode is within the SP value, t he Engine Control System is confirmed OK. When the
value in “SPEC” in “DATA MONITOR” mode is NOT wit hin the SP value, the Engine Control System may have
one or more malfunctions.
The SP value is used to detect malfunctions that may affect the Engine Control System, but will not illuminate
the MIL.
The SP value will be displayed for the following items:
 B/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board correc- tion)
 A/F ALPHA-B1/B2 (The mean value of air-fuel ratio feedback correction factor per cycle)
 MAS A/F SE-B1/B2 (The signal voltage of the mass air flow sensor)
 IDLE FUEL PRES MAX/MIN (the signal voltage of the fuel rail pressure sensor)
Component Function CheckINFOID:0000000006217761
1.PRECONDITIONING
Check that all of the following conditions are satisfied.
TESTING CONDITION
 Vehicle driven distance: More than 5,000 km (3,107 miles)
 Barometric pressure: 98.3 - 104.3 kPa (0.983 - 1.043 bar, 1.003 - 1.064 kg/cm
2, 14.25 - 15.12 psi)
 Atmospheric temperature: 20 - 30 °C (68 - 86 °F)
 Engine coolant temperature: 75 - 95 °C (167 - 203 °F)
 Transmission: Warmed-up
- After the engine is warmed up to normal operating temperat ure, drive vehicle until “ATF TEMP 2” (A/T fluid
temperature sensor signal) indicates more than 60 °C (140 °F).
 Electrical load: Not applied
- Rear window defogger switch, air conditioner switch and li ghting switch are OFF. Steering wheel is straight
ahead.
 Engine speed: Idle
 Gear position: Neutral ( or parking)
>> GO TO 2.
2.PERFORM SPEC IN DATA MONITOR MODE
WITH CONSULT-III
NOTE:
Perform “SPEC” in “DATA MONITOR” mode in maximum scale display.
1. Perform EC-139, "
Work Procedure".
2. Select “B/FUEL SCHDL”, “A/F ALPHA-B1”, “A/F ALPHA-B2”, “MAS A/F SE-B1” in “SPEC” of “DATA
MONITOR” mode with CONSULT-III.
3. Check that monitor items are within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO >> Proceed to EC-162, "
Diagnosis Procedure".
Revision: 2010 May2011 QX56