2004 INFINITI QX56 charging

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STARTING & CHARGING SYSTEM
K ELECTRICAL
CONTENTS
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SECTION SC
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Revision: August 20072004 QX56 PRECAUTIONS .......................................................... 2
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 2
Wiring Diagrams and Trouble Diagnosis .................. 2
PREPARATION ........................................................... 3
Special Service Tool ................................................. 3
Commercial Service Tools ........................................ 3
BATTERY .................................................................... 4
How to Handle Battery ............................................. 4
METHODS OF PREVENTING OVER-DIS-
CHARGE ............................................................... 4
CHECKING ELECTROLYTE LEVEL .................... 4
SPECIFIC GRAVITY CHECK ............................... 5
CHARGING THE BATTERY ................................. 6
Trouble Diagnoses with Battery/Starting/Charging
System Tester .......................................................... 6
DIAGNOSTIC RESULT ITEM CHART .................. 8
Removal and Installation .......................................... 9
REMOVAL ............................................................. 9
INSTALLATION ..................................................... 9
STARTING SYSTEM ................................................ 10
System Description ................................................ 10
Wiring Diagram — START — ..................................11
Trouble Diagnoses with Battery/Starting/Charging
System Tester ........................................................ 12
DIAGNOSTIC RESULT ITEM CHART ................ 12
WORK FLOW ...................................................... 13DIAGNOSTIC PROCEDURE 1 ........................... 14
DIAGNOSTIC PROCEDURE 2 ........................... 15
MINIMUM SPECIFICATION OF CRANKING
VOLTAGE REFERENCING COOLANT TEM-
PERATURE ......................................................... 16
Removal and Installation ........................................ 16
REMOVAL ........................................................... 16
INSTALLATION ................................................... 16
CHARGING SYSTEM ............................................... 17
System Description ................................................. 17
Wiring Diagram — CHARGE — ............................. 18
Trouble Diagnoses with Battery/Starting/Charging
System Tester ......................................................... 19
DIAGNOSTIC RESULT ITEM CHART ................ 20
WORK FLOW ...................................................... 21
DIAGNOSTIC PROCEDURE 1 ........................... 22
DIAGNOSTIC PROCEDURE 2 ........................... 23
DIAGNOSTIC PROCEDURE 3 ........................... 23
DIAGNOSTIC PROCEDURE 4 ........................... 25
DIAGNOSTIC PROCEDURE 5 ........................... 26
MALFUNCTION INDICATOR .............................. 27
Removal and Installation ........................................ 27
REMOVAL ........................................................... 27
INSTALLATION ................................................... 27
SERVICE DATA AND SPECIFICATIONS (SDS) ...... 28
Battery .................................................................... 28
Starter ..................................................................... 28
Generator ............................................................... 28

PREPARATION
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Revision: August 20072004 QX56
PREPARATIONPFP:00002
Special Service ToolEKS00793
Commercial Service ToolsEKS00794
Tool number
(Kent-Moore No.)
Tool nameDescription
—
(J-44373)
Battery/Starting/Charging system
testerTesting battery/starting/charging system
Model 620
SEL403X
Tool nameDescription
Power toolLoosening bolts and nuts
PBIC0190E

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BATTERY
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BATTERYPFP:AYBGL
How to Handle BatteryEKS00795
CAUTION:

If it becomes necessary to start the engine with a booster battery and jumper cables, use a 12-volt
booster battery.

After connecting battery cables, ensure that they are tightly clamped to battery terminals for good
contact.

Never add distilled water through the hole used to check specific gravity.
METHODS OF PREVENTING OVER-DISCHARGE
The following precautions must be taken to prevent over-discharging
a battery.

The battery surface (particularly its top) should always be kept
clean and dry.

The terminal connections should be clean and tight.

At every routine maintenance, check the electrolyte level.
This also applies to batteries designated as “low maintenance”
and “maintenance-free”.

When the vehicle is not going to be used over a long period of
time, disconnect the negative battery terminal.

Check 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 LEVEL
WAR NIN G:
Do not allow battery fluid to come in contact with skin, eyes, fabrics, or painted surfaces. After touch-
ing a battery, do not touch or rub your eyes until you have thoroughly washed your hands. If acid con-
tacts eyes, skin or clothing, immediately flush with water for 15 minutes and seek medical attention.
MEL040F
MEL041F
MEL042F

BATTERY
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Revision: August 20072004 QX56

Remove the cell plug using a suitable tool.

Add distilled water up to the MAX level.
Sulphation
A 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 “sulphated”, note its voltage
and current when charging it. As shown in the figure, less cur-
rent 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.
SPECIFIC GRAVITY CHECK
1. Read hydrometer and thermometer indications at eye level.
2. Use the following chart to correct your hydrometer reading
according to electrolyte temperature.
Hydrometer Temperature Correction
MEL043F
PKIA2353E
MEL0 42 FA
Battery electrolyte temperature °C (°F) 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)−0.004
16 (60)−0.008
10 (50)−0.012
4 (40)−0.016
−1 (30)−0.020
−7 (20)−0.024

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BATTERY
Revision: August 20072004 QX56
CHARGING THE BATTERY
CAUTION:

Do not “quick charge” a fully discharged battery.

Keep the battery away from open flame while it is being charged.

When 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.

If battery electrolyte temperature rises above 55°C (131°F), stop charging. Always charge battery
at a temperature below 55°C (131°F).
Charging Rates
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 indi-
cates 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.

If, after charging, the specific gravity of any two cells varies more than 0.050, the battery should be
replaced.
Trouble Diagnoses with Battery/Starting/Charging System TesterEKS00796
CAUTION:
When working with batteries, always wear appropriate eye protection.
NOTE:

To ensure a complete and thorough diagnosis, the battery, starter and generator test segments must be
done as a set from start to finish.

If battery surface charge is detected while testing, the tester will prompt you to turn on the headlights to
remove the surface charge.

If necessary, the tester will prompt you to determine if the battery temperature is above or below 0°C
(32°F). Choose the appropriate selection by pressing the up or down arrow button, then press “ENTER” to
make the selection.
−12 (10)−0.028
−18 (0)−0.032
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 Battery electrolyte temperature °C (°F) Add to specific gravity reading
Amps Time
50 1 hour
25 2 hours
10 5 hours
5 10 hours

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BATTERY
Revision: August 20072004 QX56
8. Press “ENTER”, then test output code is displayed. Record the
test output code on the repair order.
9. Toggle back to the “DIAGNOSTIC SCREEN” for test results.
NOTE:

If 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 “ENTER” button to make the selection.

When testing a battery installed in a vehicle that has recently
been driven, select “BEFORE CHARGE”.

If the battery has just been slow charged due to a “CHARGE
& RETEST” decision by the tester, and the tester asks the user “BEFORE CHARGE/AFTER
CHARGE”, select “AFTER CHARGE”.
DIAGNOSTIC RESULT ITEM CHART
SEL576X
Diagnostic item Service procedure
GOOD BATTERYBattery is OK. Refer to SC-6, "
Trouble Diagnoses with Battery/Starting/Charging System
Te s t e r" .
REPLACE BATTERYReplace battery.
Before replacing battery, clean the battery cable clamps and battery posts. Perform battery
test again with Battery/Starting/Charging system tester. If second test result is “Replace Bat-
tery”, 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.) Per-
form 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 “BEFORE CHARGE/AFTER CHARGE”, select “AFTER
CHARGE”.

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STARTING SYSTEM
Revision: August 20072004 QX56
Trouble Diagnoses with Battery/Starting/Charging System TesterEKS0079A
NOTE:
To ensure a complete and thorough diagnosis, the battery, starter and generator test segments must be done
as a set from start to finish.
1. Turn off all loads on the vehicle electrical system.
2. Perform battery test with Battery/Starting/Charging system
tester. Refer to SC-12, "
Trouble Diagnoses with Battery/Starting/
Charging System Tester" .
3. Press “ENTER” to begin the starting system test.
4. Start the engine.
5. Diagnosis result is displayed on the tester. Refer to SC-12,
"DIAGNOSTIC RESULT ITEM CHART" .
NOTE:

If the starter performs normally but the engine does not start,
perform engine diagnosis.

For intermittent “NO CRANK” or “NO STARTER OPERA-
TION” incidents, refer to SC-15, "
DIAGNOSTIC PROCE-
DURE 2" .
DIAGNOSTIC RESULT ITEM CHART
SEL408X
SEL409X
SEL410X
Diagnostic item Service procedure
CRANKING VOLTAGE NORMAL Go to SC-13, "
WORK FLOW" .
CRANKING VOLTAGE LOW Go to SC-13, "
WORK FLOW" .
CHARGE BATTERYPerform the slow battery charging procedure. (Initial rate of charge is 10A for 12 hours.) Per-
form battery test again with Battery/Starting/Charging system tester. Refer to SC-12, "
Trouble
Diagnoses with Battery/Starting/Charging System Tester" .
REPLACE BATTERYBefore replacing battery, clean the battery cable clamps and battery posts. Perform battery
test again with Battery/Starting/Charging system tester. Refer to SC-12, "
Trouble Diagnoses
with Battery/Starting/Charging System Tester" . If second test result is “REPLACE BAT-
TERY”, then do so. Perform battery test again to confirm repair.

CHARGING SYSTEM
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CHARGING SYSTEMPFP:23100
System DescriptionEKS0079E
The generator provides DC voltage to operate the vehicle's electrical system and to keep the battery charged.
The voltage output is controlled by the IC regulator.
Power is supplied at all times to generator terminal 4 through:

10A fuse (No. 30, located in the fuse and fusible link box).
Terminal 1 supplies power to charge the battery and operate the vehicle's electrical system. Output voltage is
controlled by the IC regulator at terminal 4 detecting the input voltage. The charging circuit is protected by the
140A fusible link (letter a , located in the fusible link box).
Ground is supplied:

to generator terminal 2

through body ground E203.
With the ignition switch in the ON or START position, power is supplied:

through 10A fuse [No. 14, located in the fuse block (J/B)]

to combination meter terminal 24 for the charge warning lamp.
Ground is supplied to terminal 13 of the combination meter through terminal 3 of the generator. With power
and ground supplied, the charge warning lamp will illuminate. When the generator is providing sufficient volt-
age with the engine running, the ground is opened and the charge warning lamp will go off.
If the charge warning lamp illuminates with the engine running, a fault is indicated.