battery voltage INFINITI QX56 2008 Factory Service Manual

PCS-22
< ECU DIAGNOSIS >[IPDM E/R]
IPDM E/R (INTELLIGENT POWER DI
STRIBUTION MODULE ENGINE ROOM)
Te r m i n a lWire
color Signal name Signal
input/
output Measuring condition
Reference value(Approx.)
Igni-
tion
switch Operation or condition
1 B/Y Battery power supply Input OFF —Battery voltage
2 R Battery power supply Input OFF —Battery voltage
3 BR ECM relay Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
4 W/L ECM relay Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
6L Throttle control motor
relay Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
7 W/B ECM relay control Input — Ignition switch ON or START
0V
Ignition switch OFF or ACC Battery voltage
8 R/B Fuse 54 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
10 G Fuse 45 Output ONDaytime light system active
0V
Daytime light system inactive Battery voltage
11 Y/B A/C compressor Output ON or
START A/C switch ON or defrost A/C
switch
Battery voltage
A/C switch OFF or defrost A/C
switch 0V
12 L/W Ignition switch sup-
plied power Input —OFF or ACC
0V
ON or START Battery voltage
13 B/Y Fuel pump relay Output — Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
14 Y/R Fuse 49 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
15 LG/B Fuse 50 (VDC) Output — Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
15 GR Fuse 50 (ABS) Output — Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
16 G Fuse 51 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
17 W Fuse 55 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
19 W/R Starter motor Output START—Battery voltage
21 BR Ignition switch sup-
plied power
Input —OFF or ACC
0V
START Battery voltage
22 G Battery power supply Output OFF —Battery voltage
23 GR/W Door mirror defogger
output signal Output —When rear defogger switch is
ON
Battery voltage
When raker defogger switch is
OFF 0V
Revision: March 2010
2008 QX56

PCS
IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
PCS-23
< ECU DIAGNOSIS > [IPDM E/R]
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B A
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N24 L Cooling fan relay Output —
Conditions correct for cooling
fan operation
Battery voltage
Conditions not correct for
cooling fan operation 0V
26 P/L Headlamp aiming mo-
tors Output —Lighting
switch 2nd
position or
AUTO, head-
lamp aiming
switch in po-
sition OFF
0V
ON Battery voltage
27 W/B Fuse 38 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
30 W Fuse 53 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
32 L Wiper low speed sig-
nal OutputON or
START Wiper switch OFF
Battery voltage
LO or INT 0V
35 L/B Wiper high speed sig-
nal OutputON or
START Wiper switch OFF, LO, INT Battery voltage
HI 0V
37 Y Power generation
command signal
Output —Ignition switch ON
6.3 V
40% is set on "Active test,"
"ALTERNATOR DUTY" of
"ENGINE" 3.8 V
40% is set on "Active test,"
"ALTERNATOR DUTY" of
"ENGINE" 1.4 V
38 B Ground Input ——0V
39 L CAN-H — ON— —
40 P CAN-L — ON— —
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value(Approx.)
Igni-
tion
switch Operation or condition
JPMIA0001GB
JPMIA0002GB
JPMIA0003GB
Revision: March 2010
2008 QX56

PCS-24
< ECU DIAGNOSIS >[IPDM E/R]
IPDM E/R (INTELLIGENT POWER DI
STRIBUTION MODULE ENGINE ROOM)
41 Y/B Hood switch Input —Hood closed OFF
0V
Hood open ON Battery voltage
42 GR Oil pressure switch Input — Engine running
Battery voltage
Engine stopped 0V
43 L/Y Wiper auto stop signal Input ON or
START Wiper switch OFF, LO, INT Battery voltage
44 BR Daytime light relay
control Input ONDaytime light system active
0V
Daytime light system inactive Battery voltage
45 G/W Horn relay control Input ON When door locks are operated
using keyfob or Intelligent Key
(OFF
→ ON)* Battery voltage
→ 0V
46 GR Fuel pump relay con-
trol
Input —Ignition switch ON or START
0V
Ignition switch OFF or ACC Battery voltage
47 O Throttle control motor
relay control
Input —Ignition switch ON or START
0V
Ignition switch OFF or ACC Battery voltage
48 B/R Starter relay (trans-
mission range switch) Input
ON or
START A/T shift selector lever in "P"
or "N"
0V
A/T shift selector lever any
other position Battery voltage
49 R/L Trailer tow relay Output ON Lighting
switch must
be in the 1st
positionOFF
0V
ON Battery voltage
50 W/R Front fog lamp (LH) Output ON or
START Lighting
switch must
be in the 2nd
position
(LOW beam
is ON) and
the front fog
lamp switch OFF
0V
ON Battery voltage
51 W/R Front fog lamp (RH) Output ON or
START Lighting
switch must
be in the 2nd
position
(LOW beam
is ON) and
the front fog
lamp switch OFF
0V
ON Battery voltage
52 L LH low beam head-
lamp Output — Lighting switch in 2nd position Battery voltage
54 R/Y RH low beam head-
lamp
Output — Lighting switch in 2nd position Battery voltage
55 G LH high beam head-
lamp
Output —Lighting switch in 2nd position
and placed in HIGH or PASS
position
Battery voltage
56 L/W RH high beam head-
lamp Output —Lighting switch in 2nd position
and placed in HIGH or PASS
position Battery voltage
Te r m i n a l
Wire
co lor Si
gn

al nameSignal
input/
output Measuring condition
Reference value(Approx.)
Igni-
tion
switch Operation or condition
Revision: March 2010
2008 QX56

PCS
IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
PCS-25
< ECU DIAGNOSIS > [IPDM E/R]
C
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B A
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*: When horn reminder is ON 57 R/L
Parking, license, and
tail lamp Output ONLighting
switch 1st po-
sition OFF 0V
ON Battery voltage
59 B Ground Input ——0V
60 B/W Rear window defog-
ger relay OutputON or
START Rear defogger switch ON
Battery voltage
Rear defogger switch OFF 0V
61 BR Fuse 32 Output OFF—Battery voltage
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value(Approx.)
Igni-
tion
switch Operation or condition
Revision: March 2010
2008 QX56

PG
PG-1
ELECTRICAL & POWER CONTROL
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SECTION PG
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CONTENTS
POWER SUPPLY, GROUND & CIRCUIT ELEMENTS
PRECAUTION .......
........................................2
PRECAUTIONS .............................................. .....2
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
2
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ............................... ......
2
Precaution for Power Generation Variable Voltage
Control System ..........................................................
3
PREPARATION ............................................4
PREPARATION .............................................. .....4
Special Service Tool ........................................... ......4
Commercial Service Tool ..........................................4
BASIC INSPECTION ....................................5
BATTERY ....................................................... .....5
How to Handle Battery ........................................ ......5
Work Flow ........................................................... ......7
INSPECTION AND ADJUSTMENT .....................8
ADDITIONAL SERVICE WHEN REMOVING BAT-
TERY NEGATIVE TERMINAL ............................... ......
8
ADDITIONAL SERVICE WHEN REMOVING
BATTERY NEGATIVE TERMINAL : Special Re-
pair Requirement ................................................. ......
8
COMPONENT DIAGNOSIS ..........................9
POWER SUPPLY ROUTING CIRCUIT .......... .....9
Wiring Diagram — Battery Power Supply — ....... ......9
Wiring Diagram — Accessory Power Supply — .....17
Wiring Diagram — Ignition Power Supply — ....... ....21
Fuse .........................................................................29
Fusible Link .............................................................29
GROUND ...........................................................30
Ground Distribution ..................................................30
HARNESS .........................................................40
Harness Layout ................................................... ....40
ELECTRICAL UNITS LOCATION ....................62
Electrical Units Location ..........................................62
HARNESS CONNECTOR .................................65
Description ...............................................................65
STANDARDIZED RELAY .................................68
Description ...............................................................68
FUSE BLOCK - JUNCTION BOX (J/B) ............70
Terminal Arrangement .............................................70
FUSE, FUSIBLE LINK AND RELAY BOX ........71
Terminal Arrangement .............................................71
ON-VEHICLE REPAIR .................................73
BATTERY ..........................................................73
Removal and Installation ..................................... ....73
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... .......................................... ...
74
SERVICE DATA AND SPECIFICATIONS
(SDS) .................................................................
74
Battery ................................................................. ....74
Revision: March 2010 2008 QX56

PG
PRECAUTIONSPG-3
< PRECAUTION >
C
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G H
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B A
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5. When the repair work is completed, return the ignition switch to the
″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of al l control units using CONSULT-III.
Precaution for Power Generation Variable Voltage Control SystemINFOID:0000000001538888
CAUTION:
For this model, the battery current sensor that is installed to the negative battery cable measures the
charging/discharging current of the battery and performs various engine controls. If an electrical com-
ponent is connected directly to the negative battery terminal, the current flowing through that compo-
nent will not be measured by the battery current sensor. This condition may cause a malfunction of
the engine control system and battery discharge m ay occur. Do not connect an electrical component
or ground wire directly to the battery terminal.
Revision: March 2010 2008 QX56

PG-6
< BASIC INSPECTION >
BATTERY
• 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 chart below to correct your hydrometer reading accord- ing to electrolyte temperature.
Hydrometer Temperature Correction
MEL043F
PKIA2353E
MEL042FA
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
Revision: March 2010 2008 QX56

PG
BATTERYPG-7
< BASIC INSPECTION >
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CHARGING THE BATTERY
CAUTION:
• Never “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. Never 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 norma lly 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.
Work FlowINFOID:0000000001696240
TROUBLE DIAGNOSIS WITH BATTERY SERVICE CENTER
For battery testing, use Battery Service Center (J-48087). For details and operating instructions, refer to Tech-
nical Service Bulletin and/or Battery Service Center User Guide.
− 12 (10) −0.028
− 18 (0) −0.032
Battery electrolyte temperature [
°C ( °F)] Add to specific gravity reading
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
Amps Time
50 1 hour
25 2 hours
10 5 hours
5 10 hours
Revision: March 2010 2008 QX56

PWC-12
< COMPONENT DIAGNOSIS >
POWER SUPPLY AND GROUND CIRCUIT
COMPONENT DIAGNOSIS
POWER SUPPLY AND GROUND CIRCUIT
POWER WINDOW MAIN SWITCH
POWER WINDOW MAIN SWITCH : DescriptionINFOID:0000000001735650
• BCM supplies power.
• It operates each power window motor via corresponding power window switch and makes window move up/down when main power window and door lock/unlock switch is operated.
POWER WINDOW MAIN SWITCH : Component Function CheckINFOID:0000000001735651
Main Power Window And Door Lock/Unlock Switch
1. CHECK MAIN POWER WINDOW AND DO OR LOCK/UNLOCK SWITCH FUNCTION
Does power window motor operate with main power window and door lock/unlock switch operation?
Is the inspection result normal?
YES >> Main power window and door lock/unlock switch power supply and ground circuit are OK.
NO >> Refer to PWC-12, "
POWER WINDOW MAIN SWITCH : Diagnosis Procedure".
POWER WINDOW MAIN SWITCH : Diagnosis ProcedureINFOID:0000000001735652
Main Power Window And Door Lock/Unlo ck Switch Power Supply Circuit Check
1. CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch ON.
2. Check voltage between main power window and door lock/ unlock switch connectors (A and B) and ground.
Is the measurement value within the specification?
YES >> GO TO 3
NO >> GO TO 2
2. CHECK HARNESS CONTINUITY
1. Turn ignition switch OFF.
2. Disconnect BCM and main power window and door lock/unlock switch.
3. Check continuity between BCM connector (A) and main power window and door lock/unlock switch connectors (B and C).
4. Check continuity between BCM connector (A) and ground.
Te r m i n a l Voltage (V)(Approx.)
(+)
(–)
Main power window and
door lock/unlock switch connector Te r m i n a l
D7 (A) 10
Ground Battery voltage
D8 (B) 19
ALKIA0273ZZ
BCM connector Terminal Main power window and
door lock/unlock switch
connector Terminal Continuity
M20 (A) 68
D7 (B) 10
Ye s
69 D8 (C) 19
LIIA2215E
Revision: March 2010 2008 QX56

POWER SUPPLY AND GROUND CIRCUITPWC-13
< COMPONENT DIAGNOSIS >
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M A
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PWC
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Is the inspection result normal?
YES >> GO TO 4
NO >> Repair or replace harness.
3. CHECK GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect main power window and door lock/unlock switch.
3. Check continuity between main power window and door lock/ unlock switch connector and ground.
Is the inspection result normal?
YES >> Replace main power window and door lock/unlock switch. Refer to PWC-115, "
Removal and Installation".
NO >> Repair or replace harness.
4. CHECK BCM OUTPUT SIGNAL
1. Connect BCM.
2. Turn ignition switch ON.
3. Check voltage between BCM connector and ground.
Is the measurement value within the specification?
YES >> Replace BCM. Refer to BCS-55, "Removal and Installation".
NO >> Repair or replace harness.
FRONT POWER WINDOW SWITCH
FRONT POWER WINDOW SWITCH : DescriptionINFOID:0000000001735654
• BCM supplies power.
• Front power window motor RH will be operated if power window and door lock/unlock switch RH is operated.
FRONT POWER WINDOW SWITCH : Component Function CheckINFOID:0000000001735655
Power Window And Door Lock/Unlock Switch RH
1. CHECK FRONT POWER WINDOW MOTOR RH FUNCTION
Does front power window motor RH operate with power window and door lock/unlock switch RH operation?
Is the inspection result normal?
YES >> Power window and door lock/unlock switch RH power supply and ground circuit are OK.
NO >> Refer to PWC-13, "
FRONT POWER WINDOW SWITCH : Diagnosis Procedure".
FRONT POWER WINDOW SWIT CH : Diagnosis ProcedureINFOID:0000000001735656
Power Window And Door Lock/Unlock Switch RH Power Supply Circuit Check
BCM connectorTerminal
GroundContinuity
M20 (A) 68
No
69
Main power window and door lock/
unlock switch connector Te r m i n a l
GroundContinuity
D8 17 Yes
ALKIA0275ZZ
Te r m i n a l s
Voltage (V)
(Approx.)
(+)
(–)
BCM connector Terminal
M20 68
Ground Battery voltage
69
LIIA0917E
Revision: March 2010 2008 QX56