2008 INFINITI QX56 relay

PWC-48
< COMPONENT DIAGNOSIS >
REAR POWER VENT WINDOW RELAY (OPEN) CHECK
1. Disconnect rear power vent window switch.
2. Check continuity between rear power vent window relay (OPEN)connector M87 terminal 2 and rear power vent window switch
connector M95 terminal 3.
Is the inspection result normal?
YES >> Replace rear power vent window switch.
NO >> Repair or replace harness. 2 - 3
: Continuity should exist.
LIIA1568E
Revision: March 2010 2008 QX56

REAR POWER VENT WINDOW RELAY (CLOSE) CHECKPWC-49
< COMPONENT DIAGNOSIS >
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REAR POWER VENT WINDOW RELAY (CLOSE) CHECK
DescriptionINFOID:0000000001735707
Rear power vent windows OPEN/CLOSE by receiving the signal from rear power vent window switch.
Diagnosis ProcedureINFOID:0000000001735708
1.CHECK REAR POWER VENT WINDOW RELAY (CLOSE) POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect rear power vent window relay (CLOSE).
3. Turn ignition switch ON.
4. Check voltage between rear power vent window relay (CLOSE) connector and ground.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair or replace harness.
2.CHECK REAR POWER VENT WINDOW RELAY (CLOSE)
Check continuity between rear pow er vent window relay (CLOSE)
terminals 3 and 4, 3 and 5.
Is the inspection result normal?
YES >> GO TO 3
NO >> Replace rear power vent window relay (CLOSE).
3.CHECK REAR POWER VENT WINDOW RELAY (CLOSE) GROUND CIRCUIT
Check continuity between rear pow er vent window relay (CLOSE)
connector M89 terminal 4 and ground.
Is the inspection result normal?
YES >> GO TO 4
NO >> Repair or replace harness.
4.CHECK REAR POWER VENT WI NDOW RELAY (CLOSE) CIRCUIT
ConnectorTe r m i n a l s
Voltage (V)
(Approx.)
(+) (-)
M89 1
Ground Battery voltage
5
LIIA1565E
Terminals Condition Continuity
34 12V direct current supply
between terminals 1 and 2
No
No current supply Yes
35 12V direct current supply
between terminals 1 and 2
Ye s
No current supply No
WIIA0291E
4 - Ground: Continuity should exist.
LIIA1567E
Revision: March 2010 2008 QX56

PWC-50
< COMPONENT DIAGNOSIS >
REAR POWER VENT WINDOW RELAY (CLOSE) CHECK
1. Disconnect rear power vent window switch.
2. Check continuity between rear power vent window relay
(CLOSE) connector M89 terminal 2 and rear power vent window
switch M95 terminal 4.
Is the inspection result normal?
YES >> Replace rear power vent window switch.
NO >> Repair or replace harness. 2 - 4
: Continuity should exist.
LIIA1569E
Revision: March 2010 2008 QX56

PWC-112
< SYMPTOM DIAGNOSIS >
REAR POWER VENT WINDOWS DO NOT OPERATE
REAR POWER VENT WINDOWS DO NOT OPERATE
Diagnosis ProcedureINFOID:0000000001735756
1. CHECK BCM POWER SUPPLY AND GROUND CIRCUIT
Check BCM power supply and ground circuit.
Refer to BCS-32, "
Diagnosis Procedure".
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair or replace the malfunctioning parts.
2. CHECK REAR POWER VENT WINDOW SWITCH
Check rear power vent window switch.
Refer to PWC-44, "
Diagnosis Procedure".
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace the malfunctioning parts.
3. CHECK REAR POWER VENT WINDOW MOTOR CIRCUIT
Check rear power vent window motor circuit.
Refer to PWC-45, "
Diagnosis Procedure" and PWC-46, "Diagnosis Procedure".
Is the inspection result normal?
YES >> GO TO 4
NO >> Repair or replace the malfunctioning parts.
4. CHECK REAR POWER VENT WINDOW RELAY
Check rear power vent window relay.
Refer to PWC-47, "
Diagnosis Procedure" and PWC-49, "Diagnosis Procedure".
Is the inspection result normal?
YES >> Inspection End.
NO >> Check intermittent incident. Refer to GI-38, "
Intermittent Incident".
Revision: March 2010 2008 QX56

SCS-1
SUSPENSION
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SECTION SCS
A
B
SCS
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O PCONTENTS
SUSPENSION CONTROL SYSTEM
BASIC INSPECTION ....... .............................3
DIAGNOSIS AND REPAIR WORKFLOW ..... .....3
Work Flow ........................................................... ......3
FUNCTION DIAGNOSIS ...............................5
SUSPENSION CONTROL SYSTEM .............. .....5
System Diagram .................................................. ......5
System Description ...................................................5
Component Parts Location ........................................6
Component Description .............................................6
DIAGNOSIS SYSTEM (SUSPENSION CON-
TROL UNIT) .........................................................
7
CONSULT-III Function ..............................................7
COMPONENT DIAGNOSIS ..........................9
C1801 VEHICLE HEIGHT SENSOR .............. .....9
Description .......................................................... ......9
DTC Logic .................................................................9
Diagnosis Procedure ................................................9
C1802 COMPRESSOR RELAY .........................10
Description ..............................................................10
DTC Logic ...............................................................10
Diagnosis Procedure ..............................................10
C1803 EXHAUST SOLENOID ...........................11
Description ..............................................................11
DTC Logic ...............................................................11
Diagnosis Procedure ..............................................11
C1804 HEIGHT ADJUSTING MALFUNCTION
(COMPRESSOR) ............................................ ....
12
Description .......................................................... ....12
DTC Logic ...............................................................12
Diagnosis Procedure ..............................................12
C1805 HEIGHT ADJUSTING MALFUNCTION
(EXH SOLENOID) ..............................................
13
Description ........................................................... ....13
DTC Logic ................................................................13
Diagnosis Procedure ..............................................13
C1806 VEHICLE HEIGHT SENSOR LOCK-
ING MALFUNCTION .........................................
14
Description ........................................................... ....14
DTC Logic ................................................................14
Diagnosis Procedure ...............................................14
C1807 SENSOR 5V MALFUNCTION ...............15
Description ...............................................................15
DTC Logic ................................................................15
Diagnosis Procedure ..............................................15
C1808 INTEGRAL TIME MALFUNCTION
SUPPLYING AIR ...............................................
16
Description ...............................................................16
DTC Logic ................................................................16
Diagnosis Procedure ..............................................16
POWER SUPPLY AND GROUND CIRCUIT ....17
SUSPENSION CONTROL UNIT ................................17
SUSPENSION CONTROL UNI T : Diagnosis Pro-
cedure .................................................................. ....
17
SUSPENSION AIR COMPRESSOR ..........................17
SUSPENSION AIR COMPRESSOR : Diagnosis
Procedure ............................................................ ....
17
HEIGHT SENSOR .................................................. ....18
HEIGHT SENSOR : Diagnosis Procedure ..............18
COMPRESSOR MOTOR RELAY .....................20
Description ...............................................................20
Component Function Check ....................................20
Diagnosis Procedure ...............................................20
HEIGHT SENSOR SIGNAL CIRCUIT ...............22
Description ...............................................................22
Component Function Check ....................................22
Diagnosis Procedure ...............................................22
Revision: March 2010 2008 QX56

SUSPENSION CONTROL SYSTEMSCS-5
< FUNCTION DIAGNOSIS >
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FUNCTION DIAGNOSIS
SUSPENSION CONTROL SYSTEM
System DiagramINFOID:0000000001731955
System DescriptionINFOID:0000000001731956
SUSPENSION CONTROL SYSTEM
The suspension control system consists of the following components
• Suspension control unit
• Compressor motor relay
• Suspension air compressor
• Exhaust valve solenoid (built into suspension air compressor)
• Height sensor
The suspension control unit monitors vehicle ride height as indicated by the height sensor. The suspension
control unit actuates the compressor motor relay to ra ise the vehicle ride height. The suspension control unit
actuates the exhaust valve solenoid to lower the vehicle ride height.
CK SUSP INDICATOR LAMP
The CK SUSP indicator lamp ground is controlled by the suspension control unit. The indicator lamp will come
on for 2 seconds when the ignition switch is turned ON. If the indicator lamp does not turn OFF there is a fault
detected. Refer to SCS-7, "
CONSULT-III Function"
ALEIA0042GB
Revision: March 2010 2008 QX56

SCS-6
< FUNCTION DIAGNOSIS >
SUSPENSION CONTROL SYSTEM
Component Parts Location
INFOID:0000000001731957
:Front
Component DescriptionINFOID:0000000001731958
1. Suspension control unit B3 (view with upper and lower luggage side finishers
LH removed) 2. Suspension air compressor C9 (view
under vehicle behind LH rear suspen-
sion) 3. Height sensor C8 (view under vehicle
at LH rear suspension)
4. Compressor motor relay E130, E131 (view with battery removed)
ALEIA0044ZZ
Part name Description
Suspension control unit • Monitors height sensor input to determine vehicle height.
• Actuates the compressor motor relay or exhaust valve solenoid to raise or
lower the vehicle accordingly.
• Sends a ground signal to the combination meter to activate the CK SUSP indicator lamp.
Suspension air compressor (with built in exhaust valve
solenoid) • When the compressor is actuated, it pumps air into the system to raise the
rear suspension.
• When the exhaust valve solenoid is actuated, it vents air from the system to lower the rear suspension.
Height sensor Provides vehicle height input to the suspension control unit.
Revision: March 2010 2008 QX56

SCS-10
< COMPONENT DIAGNOSIS >
C1802 COMPRESSOR RELAY
C1802 COMPRESSOR RELAY
DescriptionINFOID:0000000001731963
The compressor motor relay is controlled by the suspension control unit. The suspension control unit supplies
voltage to the coil side of the relay to activate it. T he compressor motor relay, when activated, supplies power
to the suspension air compressor.
DTC LogicINFOID:0000000001731964
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000001731965
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 air levelizer system com-
ponents 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"
DTCDisplay contents of CON-
SULT-III Diagnostic item is detected when ...
Probable malfunction location
C1802 COMPRESSOR RELAY • Driving transistor for the compressor
relay is
OFF and monitor voltage continues at a high
level for more than 10 seconds.
• Driving transistor for the compressor relay is
ON and monitor voltage continues at a low
level for more than 5 seconds. Compressor motor relay. Refer to
SCS-20,
"Component Function Check"
ON : Compressor turns ON
OFF : Compressor turns OFF
Revision: March 2010 2008 QX56