battery voltage INFINITI QX56 2008 Factory Service Manual

BCM (BODY CONTROL MODULE)RF-21
< ECU DIAGNOSIS >
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28 L/R Front blower monitor Input ON Front blower motor OFF Battery voltage
Front blower motor ON
0V
29 W/B Hazard switch Input OFFON
0V
OFF 5V
30 Y/BR Glass hatch switch Input OFF Glass hatch switch released
Battery voltage
Glass hatch switch pressed 0
32 R/G Combination switch
output 5
Output ONLighting, turn, wiper OFF
Wiper dial position 4
33 R/Y Combination switch
output 4 Output ONLighting, turn, wiper OFF
Wiper dial position 4
34 L Combination switch
output 3 Output ON
Lighting, turn, wiper OFF
Wiper dial position 4
35 O/B Combination switch
output 2
Output ONLighting, turn, wiper OFF
Wiper dial position 4
36 R/W Combination switch
output 1
37 B/R Key switch and igni-
tion knob switch Input OFFIntelligent Key inserted
Battery voltage
Intelligent Key inserted 0V
38 W/L Ignition switch (ON) Input ON —Battery voltage
39 L CAN-H — —— —
40 P CAN-L — —— —
42 GR Glass hatch ajar
switch Input ONGlass hatch open
0
Glass hatch closed Battery
43 R/B Back door latch (door
ajar switch) Input OFFON (open)
0V
OFF (closed) Battery voltage
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value or waveform
(Approx.)
Ignition
switch Operation or condition
SKIA5291E
SKIA5292E
SKIA5291E
SKIA5292E
Revision: March 2010
2008 QX56

RF-22
< ECU DIAGNOSIS >
BCM (BODY CONTROL MODULE)
44 ORear wiper auto stop
switch 1 Input ONRise up position (rear wiper
arm on stopper)
0V
A Position (full clockwise stop
position) Battery voltage
Forward sweep (counterclock-
wise direction) Fluctuating
B Position (full counterclock-
wise stop position) 0V
Reverse sweep (clockwise di-
rection) Fluctuating
47 SB Front door switch LH Input OFF ON (open)
0V
OFF (closed) Battery voltage
48 R/Y Rear door switch LH Input OFF ON (open)
0V
OFF (closed) Battery voltage
49 R Cargo lamp Output OFFAny door open (ON)
0V
All doors closed (OFF) Battery voltage
51 G/Y Trailer turn signal
(right) Output ON Turn right ON
52 G/B Trailer turn signal (l eft) Output ON Turn left ON
53 L/W Glass hatch lock actu-
ator
Output OFFGlass hatch switch released
0
Glass hatch switch pressed Battery
54 Y Rear wiper output cir-
cuit 2 Input ONRise up position (rear wiper
arm on stopper)
0V
A Position (full clockwise stop
position) 0V
Forward sweep (counterclock-
wise direction) 0V
B Position (full counterclock-
wise stop position) Battery voltage
Reverse sweep (clockwise di-
rection) Battery voltage
55 SB Rear wiper output cir-
cuit 1 Output ONOFF
0
ON Battery voltage
56 R/G Battery saver output Output OFF
30 minutes after ignition
switch is turned OFF 0V
ON — Battery voltage
57 Y/R Battery power supply Input OFF —Battery voltage
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value or waveform
(Approx.)
Ignition
switch Operation or condition
SKIA3009J
SKIA3009J
Revision: March 2010
2008 QX56

BCM (BODY CONTROL MODULE)RF-23
< ECU DIAGNOSIS >
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58 W/R Optical sensor Input ONWhen optical sensor is illumi-
nated
3.1V or more
When optical sensor is not illu-
minated 0.6V or less
59 G Front door lock as-
sembly LH actuator
(unlock) Output OFF
OFF (neutral)
0V
ON (unlock) Battery voltage
60 G/B Turn signal (left) Output ON Turn left ON
61 G/Y Turn signal (right) Output ON Turn right ON
62 R/W Step lamp LH and RH Output OFF ON (any door open)
0V
OFF (all doors closed) Battery voltage
63 L Interior room/map
lamp Output OFFAny door
switchON (open)
0V
OFF (closed) Battery voltage
65 V All door lock actuators
(lock) Output OFFOFF (neutral)
0V
ON (lock) Battery voltage
66 G/Y Front door lock actua-
tor RH, rear door lock
actuators LH/RH and
back door lock actua-
tor (unlock) Output OFF
OFF (neutral)
0V
ON (unlock) Battery voltage
67 B Ground Input ON—0V
68 W/L Power window power
supply (RAP) Output —Ignition switch ON
Battery voltage
Within 45 seconds after igni-
tion switch OFF Battery voltage
More than 45 seconds after ig-
nition switch OFF 0V
When front door LH or RH is
open or power window timer
operates 0V
69 W/R Power window power
supply
Output —
—Battery voltage
70 W/B Battery power supply Input OFF —Battery voltage
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value or waveform
(Approx.)
Ignition
switch Operation or condition
SKIA3009J
SKIA3009J
Revision: March 2010
2008 QX56

RF-30
< ECU DIAGNOSIS >
SUNROOF SYSTEM
SUNROOF SYSTEM
Reference ValueINFOID:0000000001731937
TERMINAL LAYOUT
PHYSICAL VALUES
LIIA2447E
Te r m i n a l N o .(Wire color) Description
ConditionVoltage (V)
(Approx.)
+ - Signal nameInput/
Output
1
(W/L) Ground RAP signal
InputIgnition switch ON
Battery voltage
Within 45 seconds after ignition
switch is turned OFF Battery voltage
When front door LH or RH is
open while retained power is op-
erating 0V
3
(P/W) Ground Sunroof switch CLOSE
signal InputIgnition switch is ON and sun-
roof switch in CLOSE position
0V
Other than above Battery voltage
4
(O) Ground Sunroof switch TILT UP
signal
InputIgnition switch is ON and sun-
roof switch in TILT UP position
0V
Other than above Battery voltage
5
(W/R) Ground BAT power supply
Input— Battery voltage
7
(B) Ground Ground
Input— Less than 0.2V
8
(Y) Ground Sunroof switch ground Output
—Less than 0.2V
9
(P) Ground
Sunroof switch OPEN sig-
nal InputIgnition switch ON and sunroof
switch in OPEN position
0V
Other than above Battery voltage
10
(L/R) Ground Sunroof switch TILT
DOWN signal InputIgnition switch ON and sunroof
switch in TILT DOWN position 0
Other than above Battery voltage
Revision: March 2010 2008 QX56

POWER SUPPLY AND GROUND CIRCUITSCS-17
< COMPONENT DIAGNOSIS >
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POWER SUPPLY AND GROUND CIRCUIT
SUSPENSION CONTROL UNIT
SUSPENSION CONTROL UNIT : Diagnosis ProcedureINFOID:0000000001731984
1.CHECK FUSES
Check that the following fuses of the sus pension control unit are not are not blown.
Are the fuses OK?
YES >> GO TO 2
NO >> If fuse is blown, be sure to eliminate cause of malfunction before installing new fuse.
2.POWER SUPPLY CIRCUIT CHECK
1. Disconnect suspension control unit connector B3.
2. Check voltage between the suspension control unit connector B3 and ground.
Are the voltage results as specified?
YES >> GO TO 3
NO >> • Check connector housings for disconnected or loose terminals. • Repair harness or connector.
3.GROUND CIRCUIT CHECK
1. Turn ignition switch OFF.
2. Check continuity between suspension control unit harness con- nector B3 and ground.
Is continuity present?
YES >> Inspection End.
NO >> Repair harness or connector.
SUSPENSION AIR COMPRESSOR
SUSPENSION AIR COMPRESSOR : Diagnosis ProcedureINFOID:0000000001731985
1.CHECK COMPRESSOR MOTOR RELAY OPRATION
CONSULT-III
Unit Terminals Signal name Fuse No.
Suspension control unit 7
Battery power 29
6 Ignition switch ON or START 12
(+)
(-) OFF ACC ON START
Connector Terminal
B3 7Ground
Battery
voltage Battery
voltage Battery
voltage Battery
voltage
6Ground0V 0V Battery
voltage Battery
voltage
ALEIA0027GB
Connector Terminal —Continuity
B3 16Ground Yes
ALEIA0028GB
Revision: March 2010 2008 QX56

SCS-18
< COMPONENT DIAGNOSIS >
POWER SUPPLY AND GROUND CIRCUIT
1. Disconnect the suspension air compressor connector C9.
2. Turn ignition switch ON.
3. Select "COMPRESSOR" under AIR LEVELIZER active testitems.
4. While operating the test item, check voltage at the suspension
air compressor connector C9 terminal 4.
Is battery voltage present?
YES >> GO TO 3.
NO >> GO TO 2.
2.COMPRESSOR MOTOR RELAY POWER SUPPLY CIRCUIT CHECK
1. Turn ignition switch OFF.
2. Disconnect the compressor motor relay connector.
3. Check continuity between compressor motor relay connector E131 (A) terminal 3 and suspension air compressor connector
C9 (B) terminal 4.
4. Check continuity between compressor motor relay connector E131 (A) terminal 3 and ground.
Are the continuity test results as specified?
YES >> Check compressor motor relay. Refer to SCS-20, "Diagnosis Procedure"
NO >> Repair harness or connector.
3.GROUND CIRCUIT CHECK
1. Turn ignition switch OFF.
2. Check continuity between suspension air compressor connector C9 terminals 1 and 3 and ground.
Is continuity present?
YES >> Inspection End.
NO >> Repair harness or connector.
HEIGHT SENSOR
HEIGHT SENSOR : Dia gnosis ProcedureINFOID:0000000001731986
1.POWER SUPPLY CIRCUIT CHECK
(+)
(-)Voltage
Connector Terminal
C9 4Ground Battery Voltage
ALEIA0021GB
AB
Continuity
Connector Terminal Connector Terminal
E131 3 C9 4 Yes
A —Con tin uit y
Connector Terminal
E131 3Ground No
ALEIA0022GB
Connector Terminal —Continuity
C9 1
Ground Yes
3
ALEIA0023GB
Revision: March 2010 2008 QX56

SCS-20
< COMPONENT DIAGNOSIS >
COMPRESSOR MOTOR RELAY
COMPRESSOR MOTOR RELAY
DescriptionINFOID:0000000001731987
Receives suspension air compressor ON signal from suspension control unit. When activated, the compressor
motor relay supplies power to the suspension air compressor.
Component Function CheckINFOID:0000000001731988
1.CHECK COMPRESSOR MOTOR RELAY OPERATION
CAUTION:
The "COMPRESSOR" active test will remain ON until it is turned off using CONSULT-III. Allowing the
compressor to run for an extended period of time may cause damage to the suspension control sys-
tem components due to excessive air pressure.
CONSULT-III
1. Turn ignition ON.
2. Select "COMPRESSOR" of AIR LEVELIZER active test items.
3. While operating test item, check that the suspension air compressor turns ON.
Does the suspension air compressor operate properly?
YES >> Compressor motor relay and suspension air compressor are operating normally.
NO >> Refer to SCS-20, "
Diagnosis Procedure"
Diagnosis ProcedureINFOID:0000000001731989
1.CHECK COMPRESSOR "ON" SIGNAL FROM SUSPENSION CONTROL UNIT
CONSULT-III
1. Turn ignition switch ON.
2. Disconnect compressor motor relay connector E130.
3. Select "COMPRESSOR" of AIR LEVELIZER active test items.
4. While operating test item, check voltage to compressor motor relay connector E130 terminal 2.
Is battery voltage present while operating test item?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK COMPRESSOR "ON" SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect suspension control unit connector B3.
3. Check continuity between suspension control unit connector B3 (A) terminal 1 and compressor motor relay connector E130 (B)
terminal 2.
4. Check continuity between suspension control unit connector B3 (A) terminal 1 and ground.ON : Compressor turns ON
OFF : Compressor turns OFF
(+)
(-)Voltage
Connector Terminal
E130 2Ground Battery voltage
ALEIA0030GB
AB
Continuity
Connector Terminal Connector Terminal
B3 1E 1302 Y es
ALEIA0031GB
Revision: March 2010 2008 QX56

COMPRESSOR MOTOR RELAYSCS-21
< COMPONENT DIAGNOSIS >
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Are the continuity test results as specified?
YES >> Replace the suspension control unit. Refer to RSU-25, "Removal and Installation"
NO >> Repair harness or connector.
3.CHECK COMPRESSOR MOTOR RELAY GROUND
1. Turn ignition switch OFF.
2. Check continuity between compressor motor relay connector E130 terminal 1 and ground.
Is continuity present?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK COMPRESSOR MOTOR RELAY POWER SUPPLY
1. Disconnect compressor motor relay connector E131.
2. Check voltage between compressor motor relay E131 terminal 5 and ground.
Is battery voltage present?
YES >> GO TO 5.
NO >> Inspect fuse and repair harness or connector.
5.CHECK COMPRESSOR MOTOR RELAY OUTPUT
1. Connect compressor motor relay connectors E130 and E131.
2. Disconnect suspension air compressor connector C9.
3. Turn ignition ON.
4. Select "COMPRESSOR" of AIR LEVELIZER active test items.
5. Check voltage between compressor motor relay C9 terminal 4 and ground.
Is battery voltage present?
YES >> Compressor motor relay is functioning properly.
NO >> GO TO 6.
6.CHECK AIR COMPRESSOR POWER SUPPLY CIRCUIT
Check the air compressor power supply circuit. Refer to SCS-17, "
SUSPENSION AIR COMPRESSOR : Diag-
nosis Procedure"
Does the power supply circuit test OK?
YES >> Replace the compessor motor relay.
NO >> Repair harness or connector.
A — Continuity
Connector Terminal
B3 1 Ground No
Connector Terminal —Continuity
E130 1Ground Yes
ALEIA0032GB
(+)
(-)Voltage
Connector Terminal
E131 5Ground Battery voltage
ALEIA0033GB
(+)
(-)Voltage
Connector Terminal
C9 4Ground Battery voltage
ALEIA0034GB
Revision: March 2010 2008 QX56

EXHAUST VALVE SOLENOID CIRCUITSCS-23
< COMPONENT DIAGNOSIS >
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EXHAUST VALVE SOLENOID CIRCUIT
DescriptionINFOID:0000000001731993
Receives exhaust valve solenoid signal from suspension control unit. When activated, the exhaust valve sole-
noid releases air pressure from the suspension control system.
Component Function CheckINFOID:0000000001731994
1.CHECK EXHAUST SOLENOID OPERATION
CAUTION:
While operating this active test, the suspension control system wil l vent air pressure and the vehicle
ride height will lower. Ensure th e area around the vehicle is free from obstructions before beginning
test.
CONSULT-III
1. Ensure the suspension control system has air pressure and is not drooping in the rear.
2. Select "EXHAUST SOLENOID" of AIR LEVELIZER active test items.
3. While operating test item, check that the exhaust va lve solenoid opens to vent air from the system. The
vehicle should lower when the exhaust valve solenoid is activated.
Does the system vent properly?
YES >> Exhaust valve solenoid is operating normally.
NO >> Refer to SCS-23, "
Diagnosis Procedure"
Diagnosis ProcedureINFOID:0000000001731995
1.CHECK EXHAUST VALVE SOLENOID SIGNAL
CONSULT-III
1. Connect suspension control unit connector B3.
2. Turn ignition switch ON.
3. Select "EXHAUST SOLENOID" of AIR LEVELIZER active test
items.
4. While test item is operating, check signal between suspension
air compressor connector C9 terminal 2 and ground.
Is battery voltage present?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK CONTINUITY OF EXHAU ST VALVE SOLENOID CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect suspension control unit connector B3 and suspen- sion air compressor connector C9.
3. Check continuity between suspension control unit connector B3
(A) terminal 9 and suspension air compressor connector C9 (B)
terminal 2.ON : Air vents and vehicle ride height lowers
OFF : No air vents and vehicle ride height remains constant
(+)
(-)Voltage
Connector Terminal
C9 2Ground Battery voltage
ALEIA0036GB
AB
Continuity
Connector Terminal Connector Terminal
B39C 92 Y es
ALEIA0037GB
Revision: March 2010 2008 QX56

SUSPENSION CONTROL UNITSCS-27
< ECU DIAGNOSIS >
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ECU DIAGNOSIS
SUSPENSION CONTROL UNIT
Reference ValueINFOID:0000000001731999
TERMINAL LAYOUT
PHYSICAL VALUES
ALNIA0660GB
Te r m i n a l
(Wire color) Description
ConditionReference value
(Approx.)
+ – Signal nameInput/
Output
1
(V) Ground Compressor relay output Output Ignition
switch
ON Air levelizer ra
ising vehicle
ride height Battery voltage
3
(W) Ground Height sensor input
InputIgnition
switch ON —
0.2V - 4.8V
5
(R) Ground VREF output (height sen-
sor) OutputIgnition
switch ON —5
V
6
(G/R) Ground IGN power supply
InputIgnition
switch
ON or
START —
Battery voltage
7
(W/L) Ground BAT power supply
InputIgnition
switch
OFF —
Battery voltage
8
(G/W) Ground Diagnostic K-line Input/
Output ——
—
9
(SB) Ground Exhaust valve output Output Ignition
switch ON Air levelizer lo
wering vehi-
cle ride height (venting) Battery voltage
10
(BR) Ground Warning lamp output Output Ignition
switch ON Warning lamp ON
0V
Warning lamp OFF Battery voltage
14
(L) Ground Height sensor ground Output Ignition
switch
ON —
Less than 0.2V
15
(BR/W) Ground Generator input
InputIgnition
switch ON Charge light ON
0V
Charge light OFF Battery voltage
16
(B) Ground Suspension control unit
ground InputIgnition
switch ON —
Less than 0.2V
Revision: March 2010 2008 QX56