2011 INFINITI QX56 ground

POWER SUPPLY AND GROUND CIRCUITDLN-93
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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POWER SUPPLY AND GROUND CIRCUIT
DescriptionINFOID:0000000006222306
Supplies power to 4WD system.
Diagnosis ProcedureINFOID:0000000006222307
1.CHECK TRANSFER CONTROL UNIT POWER SUPPLY (1)
1. Turn the ignition switch OFF.
2. Disconnect transfer control unit harness connector.
3. Check the voltage between transfer control unit harness connector and ground.
4. Turn the ignition switch ON. CAUTION:
Never start the engine.
5. Check the voltage between transfer control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK TRANSFER CONTROL UNIT POWER SUPPLY (2)
1. Turn the ignition switch OFF.
2. Check the 10A fuse (#34).
3. Check the harness for open or short between transfe r control unit harness connector No.20 terminal and
10A (#34).
Is the inspection result normal?
YES >> Perform the trouble diagnosis fo r power supply circuit. Refer to PG-11, "Wiring Diagram - BAT-
TERY POWER SUPPLY -".
NO >> Repair or replace error-detected parts.
3.CHECK TRANSFER CONTROL UNIT POWER SUPPLY (3)
1. Turn the ignition switch OFF.
2. Check the voltage between transfer control unit harness connector and ground.
3. Turn the ignition switch ON. CAUTION:
Never start the engine.
4. Check the voltage between transfer control unit harness connector and ground.
Transfer control unit — Voltage
Connector Terminal
E59 20 Ground Battery voltage
Transfer control unit — Voltage
Connector Terminal
E59 20 Ground Battery voltage
Transfer control unit — Voltage
Connector Terminal
E59 32 Ground Approx. 0 V
Transfer control unit — Voltage
Connector Terminal
E59 32 Ground Battery voltage
Revision: 2010 May2011 QX56

DLN-94
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
POWER SUPPLY AND GROUND CIRCUIT
Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 4.
4.CHECK TRANSFER CONTROL UNIT POWER SUPPLY (4)
1. Turn the ignition switch OFF.
2. Check the 10A fuse (#56).
3. Disconnect IPDM E/R harness connector.
4. Check the continuity between transfer control unit harness connector and IPDM E/R harness connector.
5. Check the continuity between transfer control unit harness connector and the ground.
Is the inspection result normal?
YES >> Perform the trouble diagnosis for ignition power supply circuit. Refer to PG-89, "Wiring Diagram -
IGNITION POWER SUPPLY -".
NO >> Repair or replace error-detected parts.
5.CHECK TRANSFER MOTOR POWER SUPPLY
1. Turn the ignition switch OFF.
2. Check the voltage between transfer control unit harness connector and ground.
3. Turn the ignition switch ON. CAUTION:
Never start the engine.
4. Check the voltage between transfer control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 6.
6.CHECK TRANSFER MOTOR POWER SUPPLY CIRCUIT
1. Turn the ignition switch OFF.
2. Check the 30A fusible link (J).
3. Check the harness for open or short between transfe r control unit harness connector No.41 terminal and
30A fusible link (J).
Is the inspection result normal?
YES >> Perform the trouble diagnosis for power supply circuit. Refer to PG-11, "Wiring Diagram - BAT-
TERY POWER SUPPLY -".
NO >> Repair or replace error-detected parts.
7.CHECK 4WD SWITCH ASSEMBLY POWER SUPPLY (1)
1. Turn the ignition switch OFF.
IPDM E/R Transfe r control unit
Continuity
Connector Terminal Connector Terminal
E15 58 E59 32 Existed
Transfer control unit —Continuity
Connector Terminal
E59 32 Ground Not existed
Transfer control unit —Voltage
Connector Terminal
E60 41 Ground Battery voltage
Transfer control unit —Voltage
Connector Terminal
E60 41 Ground Battery voltage
Revision: 2010 May2011 QX56

POWER SUPPLY AND GROUND CIRCUITDLN-95
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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2. Disconnect 4WD switch assembly harness connector.
3. Check the voltage between 4WD switch assembly harness connector and ground.
4. Turn the ignition switch ON. CAUTION:
Never start the engine.
5. Check the voltage between 4WD switch assembly harness connector and ground.
Is the inspection result normal?
YES >> GO TO 9.
NO >> GO TO 8.
8.CHECK 4WD SWITCH ASSEMBLY POWER SUPPLY (2)
1. Turn the ignition switch OFF.
2. Check the 10A fuse (#13).
3. Disconnect fuse block (J/B) harness connector.
4. Check the continuity between transfer control unit harness connector and IPDM E/R harness connector.
5. Check the continuity between transfer control unit harness connector and the ground.
Is the inspection result normal?
YES >> Perform the trouble diagnosis for ignition power supply circuit. Refer to PG-89, "Wiring Diagram -
IGNITION POWER SUPPLY -".
NO >> Repair or replace error-detected parts.
9.CHECK TRANSFER CONTROL UNIT GROUND
1. Turn the ignition switch OFF.
2. Check the voltage between transfer control unit harness connector and ground.
3. Check the continuity between transfer control unit harness connector and ground.
4WD switch assembly — Voltage
Connector Terminal
M54 12 Ground Approx. 0 V
4WD switch assembly — Voltage
Connector Terminal
M54 12 Ground Battery voltage
Fuse block (J/B) 4WD switch assembly Continuity
Connector Terminal Connector Terminal
M3 10C M54 12 Existed
4WD switch assembly —Continuity
Connector Terminal
M54 12 Ground Not existed
Transfer control unit — Voltage
Connector Terminal
E60 44
Ground Approx. 0 V
46
Transfer control unit —Continuity
Connector Terminal
E60 44
Ground Existed
46
Revision: 2010 May2011 QX56

DLN-96
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
POWER SUPPLY AND GROUND CIRCUIT
Is the inspection result normal?
YES >> GO TO 10.
NO >> Repair or replace error-detected parts.
10.CHECK 4WD SWITCH ASSEMBLY GROUND
1. Turn the ignition switch OFF.
2. Check the voltage between transfer control unit harness connector and ground.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Repair or replace error-detected parts.
4WD switch assembly —Voltage
Connector Terminal
M54 20 Ground Approx. 0 V
Revision: 2010 May2011 QX56

4WD WARNING LAMPDLN-97
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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4WD WARNING LAMP
Component Function CheckINFOID:0000000006222308
1.CHECK 4WD WARNING LAMP FUNCTION
1. Turn the ignition switch OFF to ON.
2. Check that 4WD warning lamp light up.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Proceed diagnosis procedure. Refer to DLN-97, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006222309
1.CHECK POWER SUPPLY AND GROUND CIRCUIT
Perform the trouble diagnosis for power supply and ground circuit. Refer to DLN-64, "
Diagnosis Procedure".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace the error-detected parts.
2.PERFORM SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is any DTC detected?
YES >> Check the DTC.
NO >> GO TO 3.
3.CHECK 4WD WARNING LAMP SIGNAL
With CONSULT-III
1. Turn the ignition switch ON. CAUTION:
Never start the engine.
2. Check “4WD FAIL LAMP” of CONSULT-III “DATA MONITOR” for “ALL MODE AWD/4WD”.
Does the item on
“DATA MONITOR” indicate “On”?
YES >> Check combination meter. Refer to MWI-64, "COMBINATION METER : Diagnosis Procedure".
NO >> Replace transfer control unit. Refer to DLN-107, "
Removal and Installation".
Revision: 2010 May2011 QX56

DLN-98
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
4WD INDICATOR LAMP
4WD INDICATOR LAMP
Component Function CheckINFOID:0000000006222310
1.CHECK 4WD MODE INDICATOR LAMP FUNCTION
1. Start the engine CAUTION:
Never drive the vehicle.
2. Turn the 4WD shift switch AUTO ⇒4H ⇒4LO ⇒4H ⇒AUTO.
3. Check the 4WD shift switch position (“AUTO”, “4H” and “4L”) and the indication of the 4WD mode indica-
tor lamp mutually coincide.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Proceed to diagnosis procedure. Refer to DLN-98, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006222311
1.CHECK POWER SUPPLY AND GROUND CIRCUIT
Perform the trouble diagnosis for power supply and ground circuit. Refer to DLN-64, "
Diagnosis Procedure".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace the error-detected parts.
2.CHECK 4WD WARNING LAMP SIGNAL
With CONSULT-III
1. Strat the engine.
CAUTION:
Never drive the vehicle.
2. Turn the 4WD shift switch AUTO ⇒4H ⇒4LO ⇒4H ⇒AUTO.
3. Check “4WD MODE IND” of CONSULT-III “DATA MONITOR” for “ALL MODE AWD/4WD”.
Is the inspection result normal?
YES >> Check combination meter. Refer to MWI-64, "COMBINATION METER : Diagnosis Procedure".
NO >> Replace transfer control unit. Refer to DLN-107, "
Removal and Installation".
Monitor item Condition Status
4WD MODE IND 4WD shift switch: AUTO AUTO
4WD shift switch: 4H 4H
4WD shift switch: 4L 4L
Revision: 2010 May2011 QX56

EC-3
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Work Procedure ..................................................
..
147
IDLE AIR VOLUME LEARNING ......................148
Description .......................................................... ..148
Work Procedure ....................................................148
VVEL CONTROL SHAFT POSITION SEN-
SOR ADJUSTMENT .........................................
150
Description .......................................................... ..150
Work Procedure ....................................................150
MIXTURE RATIO SELF-LEARNING VALUE
CLEAR ..............................................................
152
Description .......................................................... ..152
Work Procedure ....................................................152
FUEL PRESSURE .......................................... ..153
Work Procedure .................................................. ..153
HOW TO SET SRT CODE ................................156
Description .......................................................... ..156
SRT Set Driving Pattern ........................................157
Work Procedure ....................................................159
DTC/CIRCUIT DIAGNOSIS .......................161
TROUBLE DIAGNOSIS - SPECIFICATION
VALUE ............................................................ ..
161
Description .......................................................... ..161
Component Function Check ..................................161
Diagnosis Procedure .............................................162
POWER SUPPLY AND GROUND CIRCUIT ....168
Diagnosis Procedure ........................................... ..168
U0101 CAN COMM CIRCUIT ...........................171
DTC Logic ........................................................... ..171
Diagnosis Procedure .............................................171
U1001 CAN COMM CIRCUIT ...........................172
DTC Logic ........................................................... ..172
Diagnosis Procedure .............................................172
U0113, U1003 CAN COMM CIRCUIT ..............173
DTC Logic ........................................................... ..173
Diagnosis Procedure .............................................173
U1024 CAN COMM CIRCUIT ...........................175
DTC Logic ........................................................... ..175
Diagnosis Procedure .............................................175
P0011, P0021 IVT CONTROL ..........................177
DTC Logic ........................................................... ..177
Diagnosis Procedure .............................................178
Component Inspection (Intake Valve Timing Con-
trol Solenoid Valve) ...............................................
179
P0031, P0032, P0051, P0052 A/F SENSOR 1
HEATER ...........................................................
181
DTC Logic ........................................................... ..181
Diagnosis Procedure .............................................181
Component Inspection (A/F Sensor 1 Heater) ......182
P0037, P0038, P0057, P0058 HO2S2 HEAT-
ER ....................................................................
184
DTC Logic ............................................................ ..184
Diagnosis Procedure .............................................184
Component Inspection (HO2 Sensor 2 Heater) .....186
P006A, P0101 MAF SENSOR ........................187
DTC Logic ..............................................................187
Diagnosis Procedure .............................................188
Component Inspection (MAF Sensor) ...................190
P0075, P0081 IVT CONTROL SOLENOID
VALVE .............................................................
193
DTC Logic ..............................................................193
Diagnosis Procedure .............................................193
Component Inspection (Intake Valve Timing Con-
trol Solenoid Valve) ...............................................
194
P0087, P0088, P0090 FRP CONTROL SYS-
TEM .................................................................
195
DTC Logic ..............................................................195
Diagnosis Procedure .............................................196
Component Inspection ...........................................196
P008A LOW FUEL PRESSURE CONTROL
SYSTEM ..........................................................
198
DTC Logic ............................................................ ..198
Diagnosis Procedure .............................................198
P008B LOW FUEL PRESSURE CONTROL
SYSTEM ..........................................................
200
DTC Logic ............................................................ ..200
Diagnosis Procedure .............................................200
P0102, P0103 MAF SENSOR .........................201
DTC Logic ..............................................................201
Diagnosis Procedure .............................................201
Component Inspection (MAF Sensor) ...................203
P0106 MANIFOLD ABSOLUTE PRESSURE
SENSOR ..........................................................
206
DTC Logic ..............................................................206
Diagnosis Procedure .............................................207
Component Inspection (MAP Sensor) ...................208
P010A MANIFOLD ABSOLUTE PRESSURE
SENSOR ..........................................................
210
DTC Logic ..............................................................210
Diagnosis Procedure .............................................210
Component Inspection (MAP Sensor) ...................211
P0112, P0113 IAT SENSOR ...........................213
DTC Logic ..............................................................213
Diagnosis Procedure .............................................213
Component Inspection (Intake Air Temperature
Sensor) ..................................................................
214
P0116 ECT SENSOR ......................................215
DTC Logic ..............................................................215
Diagnosis Procedure .............................................215
Revision: 2010 May2011 QX56

EC-10
< PRECAUTION >[VK56VD]
PRECAUTIONS
CAUTION:
Comply with the following cautions to
prevent any error and malfunction.
 Install the xenon bulb securely. (Ins ufficient bulb socket installation may melt the bulb, the connec-
tor, the housing, etc. by high-v oltage leakage or corona discharge.)
 Never perform HID circuit in spection with a tester.
 Never touch the xenon bulb glass with ha nds. Never put oil and grease on it.
 Dispose of the used xenon bulb after packing it in thick vinyl without breaking it.
 Never wipe out dirt and cont amination with organic solven t (thinner, gasoline, etc.).
On Board Diagnostic (OBD) System of Engine and A/TINFOID:0000000006217652
The ECM has an on board diagnostic system. It will illuminate the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
 Always turn the ignition switch OFF and disconnect the negative battery cable before any repair or
inspection work. The open/short circuit of related sw itches, sensors, solenoid valves, etc. will cause
the MIL to illuminate.
 Always connect and lock the conn ectors securely after work. A loose (unlocked) connector will
cause the MIL to illuminate due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
 Certain systems and components, especially those related to OBD, may use a new style slide-lock-
ing type harness connector. For descripti on and how to disconnect, refer to EC-51, "
Diagnosis
Description".
 Always route and secure the harnesses properly afte r work. The interference of the harness with a
bracket, etc. may cause the MIL to illu minate due to the short circuit.
 Always connect rubber tubes properly after work. A misconnected or disconnected rubber tube may
cause the MIL to illuminate due to the malfunction of the EVAP system or fuel injection system, etc.
 Always erase the unnecessary malfunction information (repairs completed) from the ECM and TCM
(Transmission control module) before re turning the vehicle to the customer.
General PrecautionsINFOID:0000000006217653
Always use a 12 volt battery as power source.
 Never attempt to disconnect battery cables while engine is
running.
 Before connecting or disconnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative bat-
tery cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
 Before removing parts, turn ig nition switch OFF and then dis-
connect battery ground cable.
 Never disassemble ECM.
 If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to self-control at its initial value. Thus,
engine operation can vary slight ly in this case. However, this
is not an indication of a ma lfunction. Never replace parts
because of a slight variation.
 If the battery is disconnected, the following emission-related
diagnostic information will be lost within 24 hours.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
SEF289H
JMBIA0057ZZ
Revision: 2010 May2011 QX56