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Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBSC0001The Supplemental Restraint System such as ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº used along with
a seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain types of
collision. The SRS system composition which is available to INFINITI QX4 is as follows:
IFor a frontal collision
The Supplemental Restraint System consists of driver air bag module (located in the center of the steer-
ing wheel), front passenger air bag module (located on the instrument panel on passenger side), seat belt
pre-tensioners, a diagnosis sensor unit, warning lamp, wiring harness and spiral cable.
IFor a side collision
The Supplemental Restraint System consists of side air bag module (located in the outer side of front seat),
satellite sensor, diagnosis sensor unit (one of components of air bags for a frontal collision), wiring harness,
warning lamp (one of components of air bags for a frontal collision).
Information necessary to service the system safely is included in theRS sectionof this Service Manual.
WARNING:
ITo avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be performed
by an authorized INFINITI dealer.
IImproper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the RS section.
IDo not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. Spiral cable and wiring harnesses covered with yellow insulation tape either just
before the harness connectors or for the complete harness are related to the SRS.
Wiring Diagrams and Trouble DiagnosisNBSC0002When you read wiring diagrams, refer to the following:
IGI-11, ªHOW TO READ WIRING DIAGRAMSº
IEL-9, ªPOWER SUPPLY ROUTINGº for power distribution circuit
When you perform trouble diagnosis, refer to the following:
IGI-35, ªHOW TO FOLLOW TEST GROUP IN TROUBLE DIAGNOSISº
IGI-24, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENTº
PRECAUTIONS
Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
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Special Service ToolNBSC0017
Tool number
Tool nameDescription
J-44373 Model 620
Battery/Starting/Charging
system tester
SEL403X
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PREPARATION
Special Service Tool
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How to Handle BatteryNBSC0003CAUTION:
IIf it becomes necessary to start the engine with a booster
battery and jumper cables, use a 12-volt booster battery.
IAfter connecting battery cables, ensure that they are
tightly clamped to battery terminals for good contact.
INever add distilled water through the hole used to check
specific gravity.
MEL040F
METHODS OF PREVENTING OVER-DISCHARGENBSC0003S01The following precautions must be taken to prevent over-discharg-
ing a battery.
IThe battery surface (particularly its top) should always be kept
clean and dry.
IThe terminal connections should be clean and tight.
IAt every routine maintenance, check the electrolyte level.
This also applies to batteries designated as ªlow maintenanceº
and ªmaintenance-freeº.
MEL041F
IWhen the vehicle is not going to be used over a long period of
time, disconnect the negative battery terminal. (If the vehicle
has an extended storage switch, turn it off.)
MEL042F
ICheck the charge condition of the battery.
Periodically check the specific gravity of the electrolyte. Keep
a close check on charge condition to prevent over-discharge.
CHECKING ELECTROLYTE LEVELNBSC0003S02WARNING:
Do not allow battery fluid to come in contact with skin, eyes,
fabrics, or painted surfaces. After touching a battery, do not
touch or rub your eyes until you have thoroughly washed your
hands. If acid contacts eyes, skin or clothing, immediately
flush with water for 15 minutes and seek medical attention.
BATTERY
How to Handle Battery
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MEL043F
IRemove the cell plug using a suitable tool.
IAdd distilled water up to the MAX level.
SEL709E
SulphationNBSC0003S0201A battery will be completely discharged if it is left unattended
for a long time and the specific gravity will become less than
1.100. This may result in sulphation on the cell plates.
To determine if a battery has been ªsulphatedº, note its volt-
age and current when charging it. As shown in the figure, less
current and higher voltage are observed in the initial stage of
charging sulphated batteries.
A sulphated battery may sometimes be brought back into ser-
vice by means of a long, slow charge, 12 hours or more, fol-
lowed by a battery capacity test.
MEL042FA
SPECIFIC GRAVITY CHECKNBSC0003S031. Read hydrometer and thermometer indications at eye level.
2. Use the chart below to correct your hydrometer reading
according to electrolyte temperature.
Hydrometer Temperature CorrectionNBSC0003S0301
Battery electrolyte temperature ÉC (ÉF) Add to specific gravity reading
71 (160) 0.032
66 (150) 0.028
60 (140) 0.024
54 (130) 0.020
49 (120) 0.016
43 (110) 0.012
38 (100) 0.008
32 (90) 0.004
27 (80) 0
21 (70) þ0.004
16 (60) þ0.008
10 (50) þ0.012
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BATTERY
How to Handle Battery (Cont'd)
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Battery electrolyte temperature ÉC (ÉF) Add to specific gravity reading
4 (40) þ0.016
þ1 (30) þ0.020
þ7 (20) þ0.024
þ12 (10) þ0.028
þ18 (0) þ0.032
Corrected specific gravity Approximate charge condition
1.260 - 1.280 Fully charged
1.230 - 1.250 3/4 charged
1.200 - 1.220 1/2 charged
1.170 - 1.190 1/4 charged
1.140 - 1.160 Almost discharged
1.110 - 1.130 Completely discharged
CHARGING THE BATTERYNBSC0003S04CAUTION:
IDo not ªquick chargeº a fully discharged battery.
IKeep the battery away from open flame while it is being
charged.
IWhen connecting the charger, connect the leads first, then
turn on the charger. Do not turn on the charger first, as
this may cause a spark.
IIf battery electrolyte temperature rises above 60ÉC (140ÉF),
stop charging. Always charge battery at a temperature
below 60ÉC (140ÉF).
Charging RatesNBSC0003S0401
Amps Time
50 1 hour
25 2 hours
10 5 hours
5 10 hours
Do not charge at more than 50 ampere rate.
NOTE:
The ammeter reading on your battery charger will automatically
decrease as the battery charges. This indicates that the voltage of
the battery is increasing normally as the state of charge improves.
The charging amps indicated above refer to initial charge rate.
IIf, after charging, the specific gravity of any two cells varies
more than .050, the battery should be replaced.
BATTERY
How to Handle Battery (Cont'd)
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Trouble Diagnoses with
Battery/Starting/Charging System Tester
NBSC0018CAUTION:
When working with batteries, always wear appropriate eye
protection.
NOTE:
ITo ensure a complete and thorough diagnosis, the battery,
starter and alternator test segments must be done as a set
from start to finish.
IIf battery surface charge is detected while testing, the tester
will prompt you to turn on the headlights to remove the surface
charge.
IIf necessary, the tester will prompt you to determine if the bat-
tery temperature is above or below 0ÉC (32ÉF). Choose the
appropriate selection by pressing the up or down arrow button,
then press ªENTERº to make the selection.
SEL404X
1. Turn off all loads on the vehicle electrical system. Clean or
repair as necessary.
2. Visually inspect the battery, battery terminals and cable ends
with ignition switch in ªOFFº position.
NOTE:
The contact surface between the battery terminals, cable ends and
tester leads must be clean for a valid test. A poor connection will
prevent testing and a ªCHECK CONNECTIONº message will
appear during the test procedures. If this occurs, clean the battery
post and terminals, reconnect them and restart the test.
3. Connect the red tester lead clamp to the positive battery
terminal, and the black to the negative terminal.
SEL405X
4. The tester will turn on automatically. Using the arrow keys,
select ªIN VEHICLEº on the tester and then press the ªENTERº
key.
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BATTERY
Trouble Diagnoses with Battery/Starting/Charging System Tester
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SEL406X
5. Locate the battery type and rating stamped or written on the
top case of the battery to be tested.
NOTE:
The battery type and rating will have either of the following.
CCA: Cold Cranking Amps (490 CCA, 550 CCA, etc.)
JIS: Japanese Industrial Standard.
Battery is stamped with a number such as:
80D26L: 80 (rank of output), D (physical size-depth), 26 (width
in cm). The last character L (post configuration) is not input into
the tester.
The tester requires the rating for the battery be entered exactly
as it is written or stamped on the battery. Do not attempt a CCA
conversion for JIS stamped batteries. JIS must be input
directly.
6. Using the arrow and ªENTERº keys alternately, select the bat-
tery type and rating.
NOTE:
The tester lists five choices; CCA, JIS, IEC, DIN, and EN. Only use
CCA or JIS.
SEL407X
7. Press ªENTERº to begin the test. Diagnosis results are dis-
played on the tester. Refer to ªDIAGNOSTIC RESULT ITEM
CHARTº SC-9.
SEL576X
8. Press ªENTERº, then test output code is displayed. Record the
test output code on the repair order.
9. Toggle back to the ªDIAGNOSTIC SCREENº for test results.
NOTE:
IIf necessary, the tester will ask the user to determine if the
battery has just been charged. Choose the appropriate selec-
tion by pressing the up or down arrow button and then press
the ªENTERº button to make the selection.
IWhen testing a battery installed in a vehicle that has recently
been driven, select ªBEFORE CHANGEº.
IIf the battery has just been slow charged due to a ªCHARGE
& RETESTº decision by the tester, and the tester asks the user
ªBEFORE CHARGE/AFTER CHARGEº, select ªAFTER
CHARGEº.
BATTERY
Trouble Diagnoses with Battery/Starting/Charging System Tester (Cont'd)
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DIAGNOSTIC RESULT ITEM CHARTNBSC0018S01
Diagnostic item Service procedure
GOOD BATTERY Battery is OK, go to ªTrouble Diagnosesº, ªSTARTING SYSTEMº. Refer to SC-12.
REPLACE BATTERYReplace battery.
Before replacing battery, clean the battery cable clamps and battery posts. Perform bat-
tery test again with Battery/Starting/Charging system tester. If second test result is
ªReplace Batteryº, then do so. Perform battery test again to confirm repair.
BAD CELL-REPLACEReplace the battery. Perform battery test again with Battery/Starting/Charging system
tester to confirm repair.
GOOD-RECHARGEPerform the slow battery charging procedure. (Initial rate of charge is 10A for 12 hours.)
Perform battery test again with Battery/Starting/Charging system tester.
CHARGE & RETESTPerform the slow battery charging. (Initial rate of charge is 10A for 12 hours.)
Perform battery test again with Battery/Starting/Charging system tester to confirm repair.
NOTE:
If the tester asks the user ªBEFORE CHARGE/AFTER CHARGEº, select ªAFTER
CHARGEº.GI
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BATTERY
Trouble Diagnoses with Battery/Starting/Charging System Tester (Cont'd)
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