battery INFINITI QX56 2011 Factory Service Manual

GI-26
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
DescriptionINFOID:0000000006280865
Observe the following precautions to ensure safe and proper servicing. These precautions are not
described in each individual section.
Precaution for Supplemental Restraint S ystem (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006280866
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 w hether 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 inopera tive, which could increase the risk of personal injury or death in
the event of a collision that would result in air bag inflation, all maintenance must be performed by
an authorized NISS AN/INFINITI dealer.
 Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the “SRS AIR BAG”.
 Do not use electrical test equipmen t 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 minu tes before performing any service.
Precautions For Xenon Headlamp ServiceINFOID:0000000006280867
WARNING:
Comply with the following warnings to prevent any serious accident.
 Disconnect the battery cable (negative terminal) or the power supply fuse before installing, remov-
ing, or touching the xenon headlamp (bulb included). The xenon headlamp contains high-voltage
generated parts.
 Never work with wet hands.
 Check the xenon headlamp ON-OFF status after assembling it to the vehicle. Never turn the xenon
headlamp ON in other conditions. Connect th e power supply to the vehicle-side connector.
(Turning it ON outside the lamp case m ay cause fire or visual impairments.)
 Never touch the bulb glass immediately after turning it OFF. It is extremely hot.
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.).
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PRECAUTIONSGI-27
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Precaution Necessary for Steering Wh eel Rotation after Battery Disconnect
INFOID:0000000006280868
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.
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 ignition switch is turned to LOCK position.)
6. Perform self-diagnosis check of a ll control units using CONSULT-III.
Precaution for Procedure without Cowl Top CoverINFOID:0000000006280869
When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc.
General PrecautionsINFOID:0000000006280870
 Do not operate the engine for an extended period of time without
proper exhaust ventilation.
Keep the work area well ventilated and free of any inflammable
materials. Special care should be taken when handling any inflam-
mable or poisonous materials, such as gasoline, refrigerant gas,
etc. When working in a pit or ot her enclosed area, be sure to prop-
erly ventilate the area before working with hazardous materials.
Do not smoke while working on the vehicle.
PIIB3706J
SGI285
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GI-28
< PRECAUTION >
PRECAUTIONS
 Before jacking up the vehicle, apply wheel chocks or other tireblocks to the wheels to prevent t he vehicle from moving. After jack-
ing up the vehicle, support the vehicle weight with safety stands at
the points designated for proper lifting before working on the vehi-
cle.
These operations should be done on a level surface.
 When removing a heavy component such as the engine or tran- saxle/transmission, be careful not to lose your balance and drop
them. Also, do not allow them to strike adjacent parts, especially
the brake tubes and master cylinder.
 Before starting repairs which do not require battery power: Turn off ignition switch.
Disconnect the negative battery terminal.
 If the battery terminals are disconnected, recorded memory of
radio and each control unit is erased.
 To prevent serious burns: Avoid contact with hot metal parts.
Do not remove the radiator cap when the engine is hot.
 Dispose of drained oil or the solvent used for cleaning parts in an appropriate manner.
 Do not attempt to top off the fuel tank after the fuel pump nozzle
shuts off automatically.
Continued refueling may cause fuel overflow, resulting in fuel spray
and possibly a fire.
 Clean all disassembled parts in the designated liquid or solvent prior to inspection or assembly.
 Replace oil seals, gaskets, packings, O-rings, locking washers,
cotter pins, self-locking nuts, etc. with new ones.
 Replace inner and outer races of tapered roller bearings and needle bearings as a set.
 Arrange the disassembled parts in accordance with their assembled locations and sequence.
 Do not touch the terminals of electrical com ponents which use microcomputers (such as ECM).
Static electricity may damage internal electronic components.
 After disconnecting vacuum or air hoses, atta ch a tag to indicate the proper connection.
 Use only the fluids and lubricants specified in this manual.
 Use approved bonding agent, sealants or their equivalents when required.
 Use hand tools, power tools (disassembly only) and recommended special tools where specified for safe and efficient service repairs.
 When repairing the fuel, oil, water, vacuum or exhaust systems, check all affected lines for leakage.
SGI231
SEF289H
SGI233
JPAIA0335ZZ
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 Before servicing the vehicle: Protect fenders, upholstery and carpeting with appropriate covers.
Take caution that keys, buckles or buttons do not scratch paint.
WARNING:
To prevent ECM from storing the diagnostic trou ble codes, never carelessly disconnect the harness
connectors which are related to the engine cont rol system and TCM (transmission control module)
system. The connectors should be disconnected only when working according to the WORK FLOW of
TROUBLE DIAGNOSES in EC and TM sections.
Three Way CatalystINFOID:0000000006280871
If a large amount of unburned fuel flows into the catalyst , the catalyst temperature will be excessively high. To
prevent this, follow the instructions.
 Use unleaded gasoline only. Leaded gasoline will seriously damage the three way catalyst.
 When checking for ignition spark or measuring engine compression, make tests quickly and only when nec- essary.
 Do not run engine when the fuel tank level is low, otherwise the engine may misfire, causing damage to the
catalyst.
Do not place the vehicle on flammable material. Keep flammable material off the exhaust pipe and the three
way catalyst.
Multiport Fuel Inje ction System or Engine Control SystemINFOID:0000000006280872
 Before connecting or disconnecti ng any harness connector for the
multiport fuel injection system or ECM:
Turn ignition switch to “OFF” position.
Disconnect negative battery terminal.
Otherwise, there may be damage to ECM.
 Before disconnecting pressurized fuel line from fuel pump to injec- tors, be sure to release fuel pressure.
 Be careful not to jar components such as ECM and mass air flow sensor.
HosesINFOID:0000000006280873
HOSE REMOVAL AND INSTALLATION
 To prevent damage to rubber hose, do not pry off rubber hose withtapered tool or screwdriver.
SGI234
SGI787
SMA019D
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GI-36
< BASIC INSPECTION >
SERVICE INFORMATION FOR ELECTRICAL INCIDENT
BASIC INSPECTION
SERVICE INFORMATION FOR ELECTRICAL INCIDENT
Work FlowINFOID:0000000006280851
WORK FLOW
Control Units and Electrical PartsINFOID:0000000006280852
PRECAUTIONS
 Never reverse polarity of battery terminals.
 Install only parts specified for a vehicle.
 Before replacing the control unit, check the i nput and output and functions of the component parts.
 Do not apply excessive force when disconnecting a connector.
SGI838
STEP DESCRIPTION
STEP 1 Get detailed information about the conditions and the environment when the incident occurred.
The following are key pieces of information required to make a good analysis:
WHAT
Vehicle Model, Engine, Transmission/Transaxle and the System (i.e. Radio).
WHEN Date, Time of Day, Weather Conditions, Frequency.
WHERE Road Conditions, Altitude and Traffic Situation.
HOW System Symptoms, Operating Conditions
(Other Components Interaction).
Service History and if any After Market Accessories have been installed.
STEP 2 Operate the system, road test if necessary.
Verify the parameter of the incident.
If the problem cannot be duplicated, refer to “Incident Simulation Tests”.
STEP 3 Get the proper diagnosis materials together including:
 Power Supply Routing
 System Operation Descriptions
 Applicable Service Manual Sections
 Check for any Service Bulletins
Identify where to begin diagnosis based upon your knowledge of the system operation and the customer comments.
STEP 4 Inspect the system for mechanical binding, loose connectors or wiring damage.
Determine which circuits and components are involved and diagnose using the Power Supply Routing and Harness Lay-
outs.
STEP 5 Repair or replace the incident circuit or component.
STEP 6 Operate the system in all modes. Verify the system works properly under all conditions. check you have not inadvertently
created a new incident during your diagnosis or repair steps.
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SERVICE INFORMATION FOR ELECTRICAL INCIDENTGI-37
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 Do not apply excessive shock to the control unit by dropping or hit- ting it.
 Be careful to prevent condensation in the control unit due to rapid
temperature changes and do not let water or rain get on it. If water
is found in the control unit, dry it fully and then install it in the vehi-
cle.
 Be careful not to let oil to get on the control unit connector.
 Avoid cleaning the control unit with volatile oil.
 Do not disassemble the contro l unit, and do not remove the upper
and lower covers.
 When using a DMM, be careful not to let test probes get close to each other to prevent the power transistor in the control unit from
damaging battery voltage because of short circuiting.
 When checking input and output signals of the control unit, use the
specified check adapter.
How to Check TerminalINFOID:0000000006280853
CONNECTOR AND TERMINAL PIN KIT
 Use the connector and terminal pin kits listed below when replacing connectors or terminals.
 The connector and terminal pin kits contain some of the most commonly used NISSAN/INFINITI connectors
and terminals. For detailed connector and terminal pin r eplacement procedures, refer to the latest NISSAN/
INFINITI CONNECTOR AND TERMINAL PIN SERVICE MANUAL.
SAIA0255E
SEF348N
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SERVICE INFORMATION FOR ELECTRICAL INCIDENTGI-43
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Circuit InspectionINFOID:0000000006280855
DESCRIPTION
 In general, testing electrical circuits is an easy task if it is approached in a logical and organized method. Before beginning it is important to have all available information on the system to be tested. Also, get a thor-
ough understanding of system operation. Then you will be able to use the appropriate equipment and follow
the correct test procedure.
 You may have to simulate vehicle vibrations while te sting electrical components. Gently shake the wiring
harness or electrical component to do this.
NOTE:
Refer to GI-37, "
How to Check Terminal" to probe or check terminal.
TESTING FOR “OPENS” IN THE CIRCUIT
Before you begin to diagnose and test the system, you should rough sketch a schematic of the system. This
will help you to logically walk through the diagnosis process. Drawing the sketch will also reinforce your work-
ing knowledge of the system.
Continuity Check Method
The continuity check is used to find an open in the circui t. The digital multimeter (DMM) set on the resistance
function will indicate an open circuit as over limit (no beep tone or no ohms symbol). Check to always start with
the DMM at the highest resistance level.
To help in understanding the diagnosis of open circui ts, please refer to the previous schematic.
 Disconnect the battery negative cable.
 Start at one end of the circuit and work your way to the other end. (At the fuse block in this example)
 Connect one probe of the DMM to the fuse block terminal on the load side.
 Connect the other probe to the fuse block (power) side of SW1. Little or no resistance will indicate that por-
tion of the circuit has good continuity. If there were an open in the circuit, the DMM would indicate an over
limit or infinite resistance condition. (point A)
 Connect the probes between SW1 and the relay. Little or no resistance will indicate that portion of the circuit
has good continuity. If there were an open in the circuit, t he DMM would indicate an over limit or infinite resis-
tance condition. (point B)
 Connect the probes between the relay and the solenoid. Little or no resistance will indicate that portion of the
circuit has good continuity. If there were an open in the ci rcuit, the DMM would indicate an over limit or infi-
nite resistance condition. (point C)
Any circuit can be diagnosed using the approach in the previous example.
Voltage Check Method
To help in understanding the diagnosis of open circui ts please refer to the previous schematic.
In any powered circuit, an open can be found by methodica lly checking the system for the presence of voltage.
This is done by switching the DMM to the voltage function.
 Connect one probe of the DMM to a known good ground.
 Begin probing at one end of the circuit and work your way to the other end.
 With SW1 open, probe at SW1 to check for voltage. voltage: open is further down the circuit than SW1.
OPEN A circuit is open when there is no continuity through a section of the circuit.
SHORT There are two types of shorts.
 SHORT CIRCUIT
When a circuit contacts another circuit and causes the normal resistance to
change.
 SHORT TO GROUND When a circuit contacts a ground source and grounds the circuit.
SGI846-A
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GI-44
< BASIC INSPECTION >
SERVICE INFORMATION FOR ELECTRICAL INCIDENT
no voltage: open is between fuse block and SW1 (point A).
 Close SW1 and probe at relay. voltage: open is further down the circuit than the relay.
no voltage: open is between SW1 and relay (point B).
 Close the relay and probe at the solenoid. voltage: open is further down the circuit than the solenoid.
no voltage: open is between relay and solenoid (point C).
Any powered circuit can be diagnosed using the approach in the previous example.
TESTING FOR “SHORTS” IN THE CIRCUIT
To simplify the discussion of shorts in the sy stem, please refer to the following schematic.
Resistance Check Method
 Disconnect the battery negative cable and remove the blown fuse.
 Disconnect all loads (SW1 open, relay disconnected and solenoid disconnected) powered through the fuse.
 Connect one probe of the DMM to the load side of the fuse terminal. Connect the other probe to a known
good ground.
 With SW1 open, check for continuity. continuity: short is between fuse terminal and SW1 (point A).
no continuit: short is further down the circuit than SW1.
 Close SW1 and disconnect the relay. Put probes at the load side of fuse terminal and a known good ground. Then, check for continuity.
continuity: short is between SW1 and the relay (point B).
no continuity: short is further down the circuit than the relay.
 Close SW1 and jump the relay contacts with jumper wir e. Put probes at the load side of fuse terminal and a
known good ground. Then, check for continuity.
continuity: short is between relay and solenoid (point C).
no continuity: check solenoid, retrace steps.
Voltage Check Method
 Remove the blown fuse and disconnect all loads (i .e. SW1 open, relay disconnected and solenoid discon-
nected) powered through the fuse.
 Turn the ignition switch to the ON or START position. Verify battery voltage at the battery + side of the fuse
terminal (one lead on the battery + terminal side of the fuse block and one lead on a known good ground).
 With SW1 open and the DMM leads across both fuse terminals, check for voltage. voltage: short is between fuse block and SW1 (point A).
no voltage: short is further down the circuit than SW1.
 With SW1 closed, relay and solenoid disconnected and the DMM leads across both fuse terminals, check for
voltage.
voltage: short is between SW1 and the relay (point B).
no voltage: short is further down the circuit than the relay.
 With SW1 closed, relay contacts jumped with fused jumper wire check for voltage. voltage: short is down the circuit of the relay or between the relay and the disconnected solenoid (point C).
no voltage: retrace steps and check power to fuse block.
GROUND INSPECTION
 Ground connections are very important to the proper operation of electrical and electronic circuits. Ground
connections are often exposed to moisture, dirt and other corrosive elements. The corrosion (rust) can
become an unwanted resistance. This unwanted resistance can change the way a circuit works.
 Electronically controlled circuits are very sens itive to proper grounding. A loose or corroded ground can
drastically affect an electronically controlled circuit. A poor or corroded ground can easily affect the circuit.
Even when the ground connection looks clean, there c an be a thin film of rust on the surface.
SGI847-A
Revision: 2010 May2011 QX56

GI-46
< BASIC INSPECTION >
SERVICE INFORMATION FOR ELECTRICAL INCIDENT
Note in the illustration that there is an excessive 4.1 volt drop between the battery and the bulb.
Measuring Voltage Drop — Step-by-Step
 The step-by-step method is most useful for isolating excessive drops in low voltage systems (such as those
in “Computer Controlled Systems”).
 Circuits in the “Computer Controlled System” operate on very low amperage.
 The (Computer Controlled) system oper ations can be adversely affected by any variation in resistance in the
system. Such resistance variation may be caused by poor connection, improper installation, improper wire
gauge or corrosion.
 The step by step voltage drop test can identify a component or wire with too much resistance.
CONTROL UNIT CIRCUIT TEST
System Description
 When the switch is ON, the control unit lights up the lamp.
CASE 1
SGI974
SAIA0258E
MGI034A
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SERVICE INFORMATION FOR ELECTRICAL INCIDENTGI-47
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INPUT-OUTPUT VOLTAGE CHART
 The voltage value is based on the body ground.
 *: If high resistance exists in the switch side circuit (caused by a single strand), terminal 1 does not detect battery voltag e. Control unit
does not detect the switch is ON even if the switch does not turn ON. Therefore, the control unit does not supply power to ligh t up the
lamp.
CASE 2
INPUT-OUTPUT VOLTAGE CHART
 The voltage value is based on the body ground.
 *: If high resistance exists in the switch side circuit (caused by a single strand), terminal 2 does not detect approx. 0 V. C ontrol unit
does not detect the switch is ON even if the switch does not turn ON. Therefore, the control unit does not control ground to li ght up the
lamp. Terminal No. Description
Condition Value (Approx.)In case of high resistance such as single
strand (V) *
+ −Signal name Input/
Output
1 Body
ground Switch Input Switch ON Battery voltage
Lower than battery voltage Approx. 8 (Ex-
ample)
Switch OFF 0 V Approx. 0
2 Body
ground Lamp Output Switch ON Battery voltage App
rox. 0 (Inoperative lamp)
Switch OFF 0 V Approx. 0
Terminal No. Description Condition Value (Approx.)In case of high resistance such as single
strand (V) *
+ −Signal name Input/
Output
1 Body
ground Lamp Output Switch ON 0 V Battery voltage (Inoperative lamp)
Switch OFF Battery voltage Battery voltage
2 Body
ground Switch Input Switch ON 0 V Higher than 0 Approx. 4 (Example)
Switch OFF 5 V Approx. 5
MGI035A
Revision: 2010 May2011 QX56