DTC INFINITI QX56 2007 Factory Service Manual

EC-120
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
*: Leaving cooling fan OFF with CONSULT-II while engine is running may cause the engine to overheat.
DTC & SRT CONFIRMATION MODE
SRT STATUS Mode
For details, refer to EC-49, "Emission-related Diagnostic Information".
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
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION• Engine: Return to the original
trouble condition
• Change the amount of fuel injec-
tion using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.• Harness and connectors
• Fuel injector
• Air fuel ratio (A/F) sensor 1
IGNITION TIM-
ING• Engine: Return to the original
trouble condition
• Timing light: Set
• Retard the ignition timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.• Perform Idle Air Volume Learning.
POWER BAL-
ANCE• Engine: After warming up, idle the
engine.
• A/C switch: OFF
• Selector lever: P or N
• Cut off each injector signal one at
a time using CONSULT-II.Engine runs rough or dies.• Harness and connectors
• Compression
• Fuel injector
• Power transistor
•Spark plug
• Ignition coil
COOLING FAN*• Ignition switch: ON
• Turn the cooling fan HI and OFF
using CONSULT-II.Cooling fan moves and stops.• Harness and connectors
• Cooling fan motor
• IPDM E/R
ENG COOLANT
TEMP• Engine: Return to the original
trouble condition
• Change the engine coolant tem-
perature using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.• Harness and connectors
• Engine coolant temperature sen-
sor
• Fuel injector
FUEL PUMP RE-
LAY• Ignition switch: ON
(Engine stopped)
• Turn the fuel pump relay ON and
OFF using CONSULT-II and lis-
ten to operating sound.Fuel pump relay makes the operat-
ing sound.• Harness and connectors
•Fuel pump relay
PURG VOL
CONT/V• Engine: After warming up, run en-
gine at 1,500 rpm.
• Change the EVAP canister purge
volume control solenoid valve
opening percent using CON-
SULT-II.Engine speed changes according to
the opening percent.• Harness and connectors
• Solenoid valve
FUEL/T TEMP
SEN• Change the fuel tank temperature using CONSULT-II.
VENT CON-
TROL/V• Ignition switch: ON
(Engine stopped)
• Turn solenoid valve ON and OFF
with the CONSULT-II and listen to
operating sound.Solenoid valve makes an operating
sound.• Harness and connectors
• Solenoid valve
V/T ASSIGN AN-
GLE• Engine: Return to the original
trouble condition
• Change intake valve timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.• Harness and connectors
• Intake valve timing control sole-
noid valve
ALTERNATOR
DUTY•Engine: Idle
• Change duty ratio using CON-
SULT-II.Battery voltage changes.• Harness and connectors
• IPDM E/R
•Alternator

TROUBLE DIAGNOSIS
EC-121
< SERVICE INFORMATION >
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*: DTC P1442 and P1456 does not apply to JA60 models but appears in DTC Work Support Mode screens.
REAL TIME DIAGNOSIS IN DATA MONITOR MODE (RECORDING VEHICLE DATA)
Description
CONSULT-II has two kinds of triggers and they can be selected by touching “SETTING” in “DATA MONITOR”
mode.
1. “AUTO TRIG” (Automatic trigger):
• The malfunction will be identified on the CONSULT-II screen in
real time.
In other words, DTC/1st trip DTC and malfunction item will be
displayed if the malfunction is detected by ECM.
At the moment a malfunction is detected by ECM, “MONITOR”
in “DATA MONITOR” screen is changed to “Recording Data ...
xx%” as shown in the figure, and the data after the malfunction
detection is recorded. Then when the percentage reached
100%, “REAL-TIME DIAG” screen is displayed. If “STOP” is
touched on the screen during “Recording Data ... xx%”,
“REAL-TIME DIAG” screen is also displayed.
The recording time after the malfunction detection and the
recording speed can be changed by “TRIGGER POINT” and
“Recording Speed”. Refer to CONSULT-II Operation Manual.
2. “MANU TRIG” (Manual trigger):
• DTC/1st trip DTC and malfunction item will not be displayed
automatically on CONSULT-II screen even though a malfunc-
tion is detected by ECM.
DATA MONITOR can be performed continuously even though
a malfunction is detected.
Operation
1. “AUTO TRIG”
• While trying to detect the DTC/1st trip DTC by performing the DTC Confirmation Procedure, be sure to
select to “DATA MONITOR (AUTO TRIG)” mode. You can confirm the malfunction at the moment it is
detected.
• While narrowing down the possible causes, CONSULT-II should be set in “DATA MONITOR (AUTO
TRIG)” mode, especially in case the incident is intermittent.
Test mode Test item Corresponding DTC No. Reference page
EVAPORATIVE
SYSTEMPURG FLOW P0441 P0441EC-354
EVP SML LEAK P0442/P1442*P0442EC-359P0455EC-408
EVP V/S LEAK P0456/P1456* P0456EC-415
PURG VOL CN/V P1444 P0443EC-366
A/F SEN1A/F SEN1 (B1) P1276 P0130EC-225A/F SEN1 (B1) P1278/P1279 P0133EC-250
A/F SEN1 (B2) P1286 P0150EC-225
A/F SEN1 (B2) P1288/P1289 P0153EC-250
HO2S2HO2S2 (B1) P0139 P0139EC-282
HO2S2 (B1) P1146 P0138EC-270
HO2S2 (B1) P1147 P0137EC-260
HO2S2 (B2) P0159 P0159EC-282
HO2S2 (B2) P1166 P0158EC-270
HO2S2 (B2) P1167 P0157EC-260
SEF705Y
SEF707X

EC-122
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
When you are inspecting the circuit by gently shaking (or twisting) the suspicious connectors, compo-
nents and harness in the DTC Confirmation Procedure, the moment a malfunction is found the DTC/1st
trip DTC will be displayed. (Refer to “INCIDENT SIMULATION TESTS” in GI-25, "
How to Perform Effi-
cient Diagnosis for an Electrical Incident".)
2. “MANU TRIG”
• If the malfunction is displayed as soon as “DATA MONITOR” is selected, reset CONSULT-II to “MANU
TRIG”. By selecting “MANU TRIG” you can monitor and store the data. The data can be utilized for fur-
ther diagnosis, such as a comparison with the value for the normal operating condition.
Generic Scan Tool (GST) FunctionINFOID:0000000003531627
DESCRIPTION
Generic Scan Tool (OBDII scan tool) complying with SAE J1978 has
8 different functions explained below.
ISO9141 is used as the protocol.
The name GST or Generic Scan Tool is used in this service manual.
FUNCTION
PBIB0197E
SEF139P
Diagnostic test mode Function
Service $01 READINESS TESTSThis diagnostic service gains access to current emission-related data values, including an-
alog inputs and outputs, digital inputs and outputs, and system status information.
Service $02 (FREEZE DATA)This diagnostic service gains access to emission-related data value which were stored by
ECM during the freeze frame. For details, refer to EC-49, "
Emission-related Diagnostic In-
formation" .
Service $03 DTCsThis diagnostic service gains access to emission-related power train trouble codes which
were stored by ECM.

EC-134
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
12.CHECK A/F SENSOR 1 FUNCTION
Perform all DTC Confirmation Procedure related with A/F sensor 1.
• For DTC P0130, P0150, refer to EC-225, "
DTC Confirmation Procedure" .
• For DTC P0131, P0151, refer to EC-234, "
DTC Confirmation Procedure" .
• For DTC P0132, P0132, refer to EC-242, "
DTC Confirmation Procedure" .
• For DTC P0133, P0153, refer to EC-250, "
DTC Confirmation Procedure" .
• For DTC P2A00, P2A03, refer to EC-588, "
DTC Confirmation Procedure" .
OK or NG
OK >> GO TO 15.
NG >> GO TO 13.
13.CHECK A/F SENSOR 1 CIRCUIT
Perform Diagnostic Procedure according to corresponding DTC.
>> GO TO 14.
14.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “DATA MONITOR (SPEC)” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> GO TO 15.
15.DISCONNECT AND RECONNECT ECM HARNESS CONNECTOR
1. Stop the engine.
2. Disconnect ECM harness connector. Check pin terminal and connector for damage, and then reconnect it.
>> GO TO 16.
16.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “DATA MONITOR (SPEC)” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> Detect malfunctioning part according to EC-90, "
Symptom Matrix Chart" .
17.CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “DATA MONITOR (SPEC)” mode, and
make sure that the indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG (More than the SP value)>>GO TO 18.
NG (Less than the SP value)>>GO TO 25.
18.DETECT MALFUNCTIONING PART
1. Check for the cause of large engine friction. Refer to the following.
- Engine oil level is too high
- Engine oil viscosity
- Belt tension of power steering, alternator, A/C compressor, etc. is excessive
- Noise from engine
PBIB2332E

EC-138
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT
DescriptionINFOID:0000000003531634
Intermittent incidents may occur. In many cases, the malfunction resolves itself (the part or circuit function
returns to normal without intervention). It is important to realize that the symptoms described in the customer's
complaint often do not recur on (1st trip) DTC visits. Realize also that the most frequent cause of intermittent
incidents occurrences is poor electrical connections. Because of this, the conditions under which the incident
occurred may not be clear. Therefore, circuit checks made as part of the standard diagnostic procedure may
not indicate the specific malfunctioning area.
Common Intermittent Incidents Report Situations
Diagnosis ProcedureINFOID:0000000003531635
1.INSPECTION START
Erase (1st trip) DTCs. Refer to EC-49, "
Emission-related Diagnostic Information" .
>> GO TO 2.
2.CHECK GROUND TERMINALS
Check ground terminals for corroding or loose connection.
Refer to EC-143, "
Ground Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
3.SEARCH FOR ELECTRICAL INCIDENT
Perform GI-25, "
How to Perform Efficient Diagnosis for an Electrical Incident", “INCIDENT SIMULATION
TESTS”.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
4.CHECK CONNECTOR TERMINALS
Refer to GI-22, "
How to Check Terminal", “HOW TO PROBE CONNECTORS”, “How to Check Enlarged Con-
tact Spring of Terminal”.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace connector.
STEP in Work Flow Situation
2 The CONSULT-II is used. The SELF-DIAG RESULTS screen shows time data other than [0] or [1t].
3 or 4 The symptom described by the customer does not recur.
5 (1st trip) DTC does not appear during the DTC Confirmation Procedure.
10 The Diagnostic Procedure for PXXXX does not indicate the malfunctioning area.

DTC U1000, U1001 CAN COMMUNICATION LINE
EC-145
< SERVICE INFORMATION >
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DTC U1000, U1001 CAN COMMUNICATION LINE
DescriptionINFOID:0000000003531639
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
On Board Diagnosis LogicINFOID:0000000003531640
*1: This self-diagnosis has the one trip detection logic.
*2: The MIL will not light up for this self-diagnosis.
*3: This self-diagnosis has the one or two trip detection logic (Models with ICC)
DTC Confirmation ProcedureINFOID:0000000003531641
1. Turn ignition switch ON and wait at least 3 seconds.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. If 1st trip DTC is detected, go to EC-146, "
Diagnosis Procedure".
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
U1000*
1
1000*1
CAN communication lineWhen ECM is not transmitting or receiving CAN
communication signal of OBD (emission-relat-
ed diagnosis) for 2 seconds or more.• Harness or connectors
(CAN communication line is open or
shorted)
U1001*2*3
1001*2*3
When ECM is not transmitting or receiving CAN
communication signal other than OBD (emis-
sion related diagnosis) for 2 seconds or more.

EC-146
< SERVICE INFORMATION >
DTC U1000, U1001 CAN COMMUNICATION LINE
Wiring Diagram
INFOID:0000000003531642
Diagnosis ProcedureINFOID:0000000003531643
Go to LAN-44, "CAN System Specification Chart".
BBWA1671E

DTC U1010 CAN COMMUNICATION
EC-147
< SERVICE INFORMATION >
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DTC U1010 CAN COMMUNICATION
DescriptionINFOID:0000000003531644
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
On Board Diagnosis LogicINFOID:0000000003531645
This self-diagnosis has the one trip detection logic.
DTC Confirmation ProcedureINFOID:0000000003531646
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. If DTC is detected, go to EC-147, "
Diagnosis Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnosis ProcedureINFOID:0000000003531647
1.INSPECTION START
With CONSULT-II
1. Turn ignition switch ON.
2. Select “SELF-DIAG RESULTS” mode with CONSULT-II.
3. Touch “ERASE”.
4.Perform DTC Confirmation Procedure.
See EC-147, "
DTC Confirmation Procedure" .
5. Is the DTC U1010 displayed again?
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3.Perform DTC Confirmation Procedure.
See EC-147, "
DTC Confirmation Procedure" .
4. Is the DTC U1010 displayed again?
Ye s o r N o
Yes >> GO TO 2.
No >>INSPECTION END
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
U1010
1010CAN communication busWhen detecting error during the initial diagno-
sis of CAN controller of ECM.•ECM
SEF058Y

EC-148
< SERVICE INFORMATION >
DTC U1010 CAN COMMUNICATION
2.REPLACE ECM
1. Replace ECM.
2. Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to
BL-117, "
ECM Re-communicating Function".
3. Perform EC-77, "
VIN Registration" .
4. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
5. Perform EC-77, "
Throttle Valve Closed Position Learning" .
6. Perform EC-78, "
Idle Air Volume Learning" .
>>INSPECTION END

DTC P0011, P0021 IVT CONTROL
EC-149
< SERVICE INFORMATION >
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DTC P0011, P0021 IVT CONTROL
DescriptionINFOID:0000000003531648
SYSTEM DESCRIPTION
*: This signal is sent to the ECM through CAN communication line
This mechanism hydraulically controls cam phases continuously with the fixed operating angle of the intake
valve.
The ECM receives signals such as crankshaft position, camshaft position, engine speed, and engine coolant
temperature. Then, the ECM sends ON/OFF pulse duty signals to the intake valve timing (IVT) control sole-
noid valve depending on driving status. This makes it possible to control the shut/open timing of the intake
valve to increase engine torque in low/mid speed range and output in high-speed range.
COMPONENT DESCRIPTION
Intake Valve Timing Control Solenoid Valve
Intake Valve Timing (IVT) control solenoid valve is activated by ON/
OFF pulse duty (ratio) signals from the ECM.
The IVT control solenoid valve changes the oil amount and direction
of flow through intake valve timing control unit or stops oil flow.
The longer pulse width advances valve angle.
The shorter pulse width retards valve angle.
When ON and OFF pulse widths become equal, the solenoid valve
stops oil pressure flow to fix the intake valve angle at the control
position.
Intake Valve Timing Control Position Sensor
Sensor Input signal to ECM function ECM Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed
Intake valve
timing controlIntake valve timing control
solenoid valve Intake valve timing control position sensor Intake valve timing signal
Engine coolant temperature sensor Engine coolant temperature
Wheel sensor Vehicle speed*
PBIB3276E
PBIB1842E