ignition INFINITI QX56 2011 Factory Service Manual

CCS
U1000 CAN COMM CIRCUITCCS-145
< DTC/CIRCUIT DIAGNOSIS > [ICC]
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U1000 CAN COMM CIRCUIT
ADAS CONTROL UNIT
ADAS CONTROL UNIT : DescriptionINFOID:0000000006227995
CAN COMMUNICATION
CAN (Controller Area Network) is a serial communication line for real time applications. It is an on-vehicle mul-
tiplex communication line with high data communicati on speed and excellent error detection ability. Modern
vehicle is equipped with many electronic control units , 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, CAN-L) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads the required data only.
CAN communication signal chart. Refer to LAN-28, "
CAN COMMUNICATION SYSTEM : CAN Communica-
tion Signal Chart".
ITS COMMUNICATION
 ITS communication is a multiplex communication syste m. This enables the system to transmit and receive
large quantities of data at high speed by connec ting control units with 2 communication lines.
 ITS communication lines adopt twisted-pair line st yle (two lines twisted) for noise immunity.
ADAS CONTROL UNIT : DTC LogicINFOID:0000000006227996
DTC DETECTION LOGIC
NOTE:
If “U1000” is detected, first diagnose the CAN communication system.
ADAS CONTROL UNIT : Diagnosis ProcedureINFOID:0000000006227997
1.PERFORM THE SELF-DIAGNOSIS
1. Turn the ignition switch ON.
2. Turn the MAIN switch of ICC system ON, and then wait for 30 seconds or more.
3. Perform “All DTC Readi ng” with CONSULT-III.
4. Check if the “U1000” is detected as the current ma lfunction in “Self Diagnostic Result” of “ICC/ADAS”.
Is
“U1000” detected as the current malfunction?
YES >> Refer to LAN-18, "Trouble Diagnosis Flow Chart".
NO >> Refer to GI-40, "
Intermittent Incident".
ICC SENSOR
ICC SENSOR : DescriptionINFOID:0000000006224409
ITS COMMUNICATION
 ITS communication is a multiplex communication syste m. This enables the system to transmit and receive
large quantities of data at high speed by connec ting control units with 2 communication lines
 ITS communication lines adopt twisted-pair line st yle (two lines twisted) for noise immunity.
ICC SENSOR : DTC LogicINFOID:0000000006224410
DTC DETECTION LOGIC
DTC
(On board
display) Trouble diagnosis name DTC detecting condition Possible causes
U1000 (100) CAN COMM CIRCUIT If ADAS control unit is not transmitting or receiv-
ing CAN communication signal or ITS communi-
cation signal for 2 seconds or more  CAN communication system
 ITS communication system
Revision: 2010 May2011 QX56

CCS-146
< DTC/CIRCUIT DIAGNOSIS >[ICC]
U1000 CAN COMM CIRCUIT
ICC SENSOR : Diagnosis Procedure
INFOID:0000000006224411
1.PERFORM THE SELF-DIAGNOSIS
1. Turn the ignition switch ON.
2. Turn the MAIN switch of ICC system ON, and then wait for 2 seconds or more.
3. Perform “All DTC Reading” with CONSULT-III.
4. Check if the “U1000” is detected as the current malfunction in “Self Diagnostic Result” of “LASER”.
Is
“U1000” detected as the current malfunction?
YES >> Refer to LAN-18, "Trouble Diagnosis Flow Chart".
NO >> Refer to GI-40, "
Intermittent Incident".
DTC Trouble diagnosis name DTC detecting condition Possible causes
U1000 CAN COMM CIRCUIT If ICC sensor is not transmitting or receiving ITS
communication signal for 2 seconds or more ITS communication system
Revision: 2010 May2011 QX56

CCS-158
< DTC/CIRCUIT DIAGNOSIS >[ICC]
POWER SUPPLY AND GROUND CIRCUIT
POWER SUPPLY AND GROUND CIRCUIT
ADAS CONTROL UNIT
ADAS CONTROL UNIT : Diagnosis ProcedureINFOID:0000000006228002
1.CHECK ADAS CONTROL UNIT POWER SUPPLY CIRCUIT
Check voltage between ADAS control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair the ADAS control unit power supply circuit.
2.CHECK ADAS CONTROL UNIT GROUND CIRCUIT
1. Turn the ignition switch OFF.
2. Disconnect the ADAS control unit connector.
3. Check for continuity between ADAS control unit harness connector and ground.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Repair the ADAS control unit ground circuit.
ICC SENSOR
ICC SENSOR : Diagnosis ProcedureINFOID:0000000006224439
1.CHECK ICC SENSOR POWER SUPPLY CIRCUIT
Check voltage between ICC sensor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair the ICC sensor power supply circuit.
2.CHECK ICC SENSOR GROUND CIRCUIT
1. Turn the ignition switch OFF.
2. Disconnect the ICC sensor connector.
Te r m i n a l Condition
Voltag e
(Approx.)
(+) (–)
ADAS control unit
GroundIgnition
switch
Connector Terminal
B61 16 OFF 0 V
ON Battery volt-
age
ADAS control unit
GroundContinuity
Connector Terminal
B61 6 Existed
Te r m i n a l Condition
Voltag e
(Approx.)
(+) (–)
ICC sensor
GroundIgnition
switch
Connector Terminal
E65 1 OFF 0 V
ON Battery volt-
age
Revision: 2010 May2011 QX56

CHG
PRECAUTIONSCHG-3
< PRECAUTION >
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental
Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006274854
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the “SRS AIR BAG” and “SEAT BELT” of this
Service Manual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision that would result in air ba g inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
 Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the “SRS AIR BAG”.
 Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
 When working near the Air Bag Diagnosis Sensor Unit or other Air Bag System sensors with the
ignition ON or engine running, DO NOT use air or electric power tools or strike near the sensor(s)
with a hammer. Heavy vibration could activate the sensor(s) and deploy the air bag(s), possibly
causing serious injury.
 When using air or electric power tools or hammers , always switch the ignition OFF, disconnect the
battery, and wait at least 3 minutes before performing any service.
Precaution Necessary for Steering Wh eel Rotation after Battery Disconnect
INFOID:0000000006274855
NOTE:
 Before removing and installing any control units, first tu rn the push-button ignition switch to the LOCK posi-
tion, then disconnect both battery cables.
 After finishing work, confirm that all control unit connectors are connected properly, then re-connect both
battery cables.
 Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If a DTC is detected, perform trouble diagnos is according to self-diagnosis results.
For vehicle with steering lock unit, if the battery is disconnected or discharged, the steering wheel will lock and
cannot be turned.
If turning the steering wheel is required with the batte ry disconnected or discharged, follow the operation pro-
cedure below before starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Turn the push-button ignition switch to ACC position. (At this time, the steering lock will be released.)
3. Disconnect both battery cables. The steering lock wil l remain released with both battery cables discon-
nected and the steering wheel can be turned.
4. Perform the necessary repair operation.
Revision: 2010 May2011 QX56

CHG-4
< PRECAUTION >
PRECAUTIONS
5. When the repair work is completed, re-connect both battery cables. With the brake pedal released, turn
the push-button ignition switch from ACC position to ON position, then to LOCK position. (The steering
wheel will lock when the push-button igniti on switch is turned to LOCK position.)
6. Perform self-diagnosis check of all control units using CONSULT-III.
Precaution for Power Generation Vo ltage Variable Control SystemINFOID:0000000006274856
CAUTION:
For this model, the battery current sensor that is in stalled to the battery cable at the negative terminal
measures the charging/discharging curre nt of the battery, and performs various controls. If the electri-
cal component or the ground wire is connected direct ly to the battery terminal, the current other than
that being measured with the battery current sensor is charging to or discharging from the battery.
This condition causes the malfunction of the control, and then the battery discharge may occur. Do
not connect the electrical compon ent or the ground wire directly to the battery terminal.
Revision: 2010 May2011 QX56

CHG-14
< BASIC INSPECTION >
DIAGNOSIS AND REPAIR WORKFLOW
NOTE:
To ensure a complete and thorough diagnosis, the battery, starter and alternator test segments must be done
as a set from start to finish.
1.PRELIMINARY INSPECTION
Perform the preliminary inspection. Refer to CHG-16, "
Inspection Procedure".
>> GO TO 2.
2.STOP POWER GENERATION VOLT AGE VARIABLE CONTROL SYSTEM
Stop the operation of the power generation voltage variabl e control in either of the following procedures.
 After selecting “ENGINE” of “SELECT SYSTEM” usi ng CONSULT-III, set the DUTY value of “ALTERNATOR
DUTY” to 0 % by selecting “ALTERNATOR DUTY” of “Active Test”. Continue “Active Test” until the end of
inspection. (When the DUTY value is 0 or 100 %, the normal power generation is performed according to the
characteristic of the IC voltage regulator of the alternator.)
 Turn the ignition switch OFF, and disconnect the batte ry current sensor connector. [However, DTC (P1550 -
P1554) of the engine might remain. After finishing the inspection, connect the battery current sensor connec-
tor and erase the self-diagnosis results history of the engine using CONSULT-III.]
>> GO TO 3.
3.DIAGNOSIS WITH STARTING /CHARGING SYSTEM TESTER
Perform the charging system test us ing Starting/Charging System Tester (SST: J-44373). For details and oper-
ating instructions, refer to Technical Service Bulletin.
Te s t r e s u l t
CHARGING SYSTEM NORMAL>>Char ging system is normal and will also show “DIODE RIPPLE” test
result.
NO CHARGING VOLTAGE>>GO TO 4.
LOW CHARGING VOLTAGE>>GO TO 12.
HIGH CHARGING VOLTAGE>>GO TO 14.
DIODE RIPPLE NORMAL>>Diode ripple is OK and will also show “CHARGING VOLTAGE” test result.
EXCESS RIPPLE DETECTED>>Replace the alternator. Perform “DIODE RIPPLE” test again using Starting/
Charging System Tester (SST : J-44373) to confirm repair.
DIODE RIPPLE NOT DETECTED>>GO TO 4.
4.INSPECTION WITH CHARGE WARNING LAMP (IGNITION SWITCH IS ON)
Turn the ignition switch ON.
Does the charge warning lamp illuminate?
YES >> GO TO 6.
NO >> GO TO 5.
5.“L” TERMINAL CIRCUIT (OPEN) INSPECTION
Check “L” terminal circuit (open). Refer to CHG-20, "
Diagnosis Procedure".
Is the
“L” terminal circuit normal?
YES >> Replace alternator.
NO >> Repair as needed.
6.INSPECTION WITH CHARGE WARNING LAMP (IDLING)
Start the engine and run it at idle.
Does the charge warning lamp turn OFF?
YES >> GO TO 9.
NO >> GO TO 7.
7.“L” TERMINAL CIRCUIT (SHORT) INSPECTION
Check “L” terminal circuit (short). Refer to CHG-22, "
Diagnosis Procedure".
Is the
“L” terminal circuit normal?
YES >> GO TO 8.
NO >> Repair as needed.
Revision: 2010 May2011 QX56

CHG-16
< BASIC INSPECTION >
CHARGING SYSTEM PRELIMINARY INSPECTION
CHARGING SYSTEM PRELIMINARY INSPECTION
Inspection ProcedureINFOID:0000000006274866
1.CHECK BATTERY TERMINALS CONNECTION
Check if battery terminals are clean and tight.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair battery terminals connection.
2.CHECK FUSE
Check for blown fuse and fusible link.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Replace the blown fuse after repairing the applicable circuit.
3.CHECK “E” TERMINAL CONNECTION
Check if “E” terminal (alternator ground harness) is clean and tight.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair “E” terminal connection.
4.CHECK DRIVE BELT TENSION
Check drive belt tension. Refer to EM-20, "
Checking".
Is the inspection result normal?
YES >> INSPECTION END
NO >> Repair as needed.
Unit Power source (Power supply terminals) Fuse No.
Alternator Battery (“S” terminal) 32
Combination meter Ignition switch ON (“L” terminal) 3
Revision: 2010 May2011 QX56

CHG
POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM OPERATION
INSPECTION
CHG-17
< BASIC INSPECTION >
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POWER GENERATION VOLTAGE VA
RIABLE CONTROL SYSTEM OPER-
ATION INSPECTION
Inspection ProcedureINFOID:0000000006274867
CAUTION:
When performing this inspection, always use a charged battery that has completed the battery inspec-
tion. (When the charging rate of the battery is low, the response speed of the voltage change will
become slow. This can cause an incorrect inspection.)
1.CHECK ECM (CONSULT-III)
Perform ECM self-diagnosis with CONSULT-III. Refer to EC-63, "
CONSULT-III Function".
Self
-diagnostic results content
No malfunction detected>> GO TO 2.
Malfunction detected>> Check applicable parts, and repair or replace corresponding parts.
2.CHECK OPERATION OF POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM
1. Connect CONSULT-III and start the engine.
2. shift the selector lever to “P” or “N” position and turn off all of the electric loads and A/C, etc.
3. Select “ALTERNATOR DUTY” at “Active Test” of “ENGINE”, and then check the value of “BATTERY
VOLT” monitor when DUTY value of “ALTERNATOR DUTY” is set to 40.0 %.
4. Check the value of “BATTERY VOLT” monitor when DUTY value of “ALTERNATOR DUTY” is set to 80.0%.
Is the measurement value within the specification?
YES >> INSPECTION END
NO >> GO TO 3.
3.CHECK IPDM E/R (CONSULT-III)
Perform IPDM E/R self-diagnosis with CONSULT-III. Refer to PCS-12, "
CONSULT-III Function (IPDM E/R)".
Self
-diagnostic results content
No malfunction detected>> GO TO 4.
Malfunction detected>> Check applicable parts, and repair or replace corresponding parts.
4.CHECK HARNESS BETWEEN ALTE RNATOR AND IPDM E/R
1. Turn ignition switch OFF.
2. Disconnect alternator harness connec tor and IPDM E/R harness connector.
3. Check continuity between alternator har ness connector and IPDM E/R harness connector.
4. Check continuity between alte rnator harness connector and ground.
“BATTERY VOLT”
2 seconds after setting the
DUTY value of “ALTERNA-
TOR DUTY” to 40.0 %
: 12 - 13.6 V
“BATTERY VOLT”
20 seconds after setting
the DUTY value of “ALTER-
NATOR DUTY” to 80.0 % : +0.5 V or more against
the value of “BATTERY
VOLT” monitor when
DUTY value is 40.0 %
Alternator IPDM E/R
Continuity
Connector Terminal Connector Terminal
E205 5 E13 33 Existed
Revision: 2010 May2011 QX56

CHG
B TERMINAL CIRCUITCHG-19
< DTC/CIRCUIT DIAGNOSIS >
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DTC/CIRCUIT DIAGNOSIS
B TERMINAL CIRCUIT
DescriptionINFOID:0000000006274868
“B” terminal circuit supplies power to charge the bat
tery and to operate the vehicle’s electrical system.
Diagnosis ProcedureINFOID:0000000006274869
1.CHECK “B” TERMINAL CONNECTION
1. Turn ignition switch OFF.
2. Check that “B” terminal is clean and tight.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair “B” terminal connection. Confirm repair by performing complete Starting/Charging system test. Refer to Technical Service Bulletin.
2.CHECK “B” TERMINAL CIRCUIT
Check voltage between alternator “B” terminal and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Check harness for open between alternator and fusible link.
3.CHECK “B” TERMINAL CONNECT ION (VOLTAGE DROP TEST)
1. Start engine, then engine running at idle and warm.
2. Check voltage between battery positive terminal and alternator “B” terminal.
Is the inspection result normal?
YES >> “B” terminal circuit is normal. Refer to CHG-13, "Work Flow".
NO >> Check harness between battery and alternator for poor continuity.
(+)
(–) Voltage
Alternator “B” terminal
E203 1 Ground Battery voltage
(+) (–)
Voltage (V)
(Approx.)
Alternator “B” terminal Terminal
Battery positive terminal E203 1 Less than 0.2
Revision: 2010 May2011 QX56

CHG-20
< DTC/CIRCUIT DIAGNOSIS >
L TERMINAL CIRCUIT (OPEN)
L TERMINAL CIRCUIT (OPEN)
DescriptionINFOID:0000000006274870
The “L” terminal circuit controls the charge warning lamp. The charge warning lamp illuminates when the igni-
tion switch is set to ON or START. When the alternat or is providing sufficient voltage with the engine running,
the charge warning lamp will go off. If the charge warn ing lamp illuminates with the engine running, a malfunc-
tion is indicated.
Diagnosis ProcedureINFOID:0000000006274871
1.CHECK “L” TERMINAL CONNECTION
1. Turn ignition switch OFF.
2. Check that “L” terminal is clean and tight.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair “L” terminal connection. Confirm repair by performing complete Starting/Charging system test. Refer to Technical Service Bulletin.
2.CHECK “L” TERMIN AL CIRCUIT (OPEN)
1. Disconnect alternator connector.
2. Apply ground to alternator harness connector terminal.
3. Check condition of the charge warning lamp with the ignition switch in the ON position.
Does it illuminate?
YES >> “L” terminal circuit is normal. Refer to CHG-13, "Work Flow".
NO >> GO TO 3.
3.CHECK HARNESS CONTI NUITY (OPEN CIRCUIT)
1. Disconnect the battery cable from the negative terminal.
2. Disconnect the combination meter connector.
3. Check continuity between alternator harness connector and combination meter harness connector.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair the harness or connector.
4.CHECK HARNESS CONTI NUITY (OPEN CIRCUIT)
Check continuity between combination me ter harness connector and fuse block (J/B).
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair the harness or connector.
5.CHECK POWER SUPPLY CIRCUIT
(+) (–) Condition Charge warning lamp
Alternator
Connector Terminal E205 3 Ground Ignition switch ON ON
Alternator Combination meter Continuity
Connector Terminal Connector Terminal
E205 3 M34 25 Existed
Combination meter Fuse block (J/B) Continuity
Connector Terminal Connector Terminal
M34 2 M1 2A Existed
Revision: 2010 May2011 QX56