relay INFINITI QX56 2011 Factory Service Manual

SCS-2
ACCUMULATOR ......................................................34
ACCUMULATOR : Exploded View .........................35
ACCUMULATOR : Removal and Installation ..........35
ACCUMULATOR : Inspection ................................38
ACCUMULATOR : Disposal ...................................38
PPMU, MIDDLE TUBE ASSEMBLY, PPMU PIPE ...38
PPMU, MIDDLE TUBE ASSEMBLY, PPMU PIPE
: Exploded View ......................................................
39
PPMU, MIDDLE TUBE ASSEMBLY, PPMU PIPE
: Removal and Installation ......................................
39
PPMU, MIDDLE TUBE ASSEMBLY, PPMU PIPE
: Inspection .............................................................
43
PPMU, MIDDLE TUBE ASSEMBLY, PPMU PIPE
: Disposal ................................................................
43
REAR TUBE ASSEMBLY ...................................... ...43
REAR TUBE ASSEMBLY : Exploded View ............44
REAR TUBE ASSEMBLY : Removal and Installa-
tion ....................................................................... ...
44
REAR TUBE ASSEMBLY : Inspection ...................46
AIR LEVELIZER CONTROL SYSTEM
PRECAUTION ....... ....................... ...............
47
PRECAUTIONS .............................................. ...47
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" .............................................................. ...
47
Precaution Necessary for Steering Wheel Rota-
tion after Battery Disconnect ..................................
47
Precaution for Procedure without Cowl Top Cover ...48
Precaution for Air Levelizer Control System ...........48
SYSTEM DESCRIPTION ............................49
DESCRIPTION ................................................ ...49
Description ........................................................... ...49
COMPONENT PARTS .......................................50
Component Parts Location .................................. ...50
Component Description ..........................................50
Air Levelizer Control Module ..................................51
Vehicle Height Sensor ............................................51
Air Compressor .......................................................51
Air Compressor Relay ............................................51
CK SUSP Indicator Lamp .......................................51
STRUCTURE AND OPERATION ......................52
Rear Shock Absorber .......................................... ...52
Vehicle Height Sensor ............................................53
SYSTEM .......................................................... ...54
System Diagram .................................................. ...54
System Description .................................................54
Fail-safe ..................................................................55
DIAGNOSIS SYSTEM (AIR LEVELIZER
CONTROL MODULE) ........................................
56
CONSULT-III Function ........................................ ...56
ECU DIAGNOSIS INFORMATION .............58
AIR LEVELIZER CONTROL MODULE .......... ...58
Reference Value .................................................. ...58
Fail-safe ..................................................................59
DTC Inspection Priority Chart .................................59
DTC Index ...............................................................59
WIRING DIAGRAM ....................................61
AIR LEVELIZER CONTROL SYSTEM ........... ...61
Wiring Diagram .................................................... ...61
BASIC INSPECTION ..................................65
DIAGNOSIS AND REPAIR WORKFLOW ...... ...65
Work Flow ............................................................ ...65
Diagnostic Work Sheet ...........................................66
STANDARD VEHICLE HEIGHT SETTING .......67
Description ........................................................... ...67
Work Procedure ......................................................67
DTC/CIRCUIT DIAGNOSIS ........................69
C1801 VHCL HEIGHT SENSOR .................... ...69
DTC Logic ............................................................ ...69
Diagnosis Procedure ..............................................69
Component Inspection ............................................70
C1802 AIR SUS COMPRS RELAY ...................72
DTC Logic ............................................................ ...72
Diagnosis Procedure ..............................................72
C1803 AIR SUSPENSION EXH SOL ................74
DTC Logic ............................................................ ...74
Diagnosis Procedure ..............................................74
Component Inspection ............................................75
C1804 VHCL HEIGHT ADJ UP .........................77
DTC Logic ............................................................ ...77
Diagnosis Procedure ..............................................77
Component Inspection (Air Compressor Relay) .....79
Component Inspection (Air Compressor) ............. ...79
C1805 VHCL HEIGHT ADJ DOWN ...................80
DTC Logic ............................................................ ...80
Diagnosis Procedure ..............................................80
C1806 VHCL HEIGHT SEN FIX ........................81
DTC Logic ............................................................ ...81
Diagnosis Procedure ...............................................81
C1807 VHCL HEIGHT SEN VOLT ....................82
DTC Logic ............................................................ ...82
Diagnosis Procedure ..............................................82
C1808 AIR SUS COMPRS FNCTN ...................84
DTC Logic ............................................................ ...84
Diagnosis Procedure ..............................................84
U1000 CAN COMM CIRCUIT ............................87
Revision: 2010 May2011 QX56

SCS-50
< SYSTEM DESCRIPTION >[AIR LEVELIZER CONTROL SYSTEM]
COMPONENT PARTS
COMPONENT PARTS
Component Parts LocationINFOID:0000000006256040
Component DescriptionINFOID:0000000006256041
1. Combination meter
Refer to MWI-6, "
METER SYSTEM
: Component Parts Location".2. CK SUSP indicator lamp 3. Air levelizer control module
4. Air compressor relay 5. Air chamber 6. Air compressor
7. Vehicle height sensor
A. Inside of luggage side finisher low- er (LH) B. Engine room (RH) C. Rear shock absorber
D. Vehicle rear (LH)
JSEIA0223GB
Component parts Reference
Air levelizer control module SCS-51, "
Air Levelizer Control Module"
Vehicle height sensorSCS-51, "Vehicle Height Sensor"
Air compressor
SCS-51, "Air Compressor"Exhaust solenoid
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COMPONENT PARTSSCS-51
< SYSTEM DESCRIPTION > [AIR LEVELIZER CONTROL SYSTEM]
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Air Levelizer Control ModuleINFOID:0000000006256042
 Operates ON/OFF of air compressor (exhaust solenoid) , according to signal from vehicle height sensor.
 Transmits CK SUSP indicator lamp signal to the combination meter via CAN communication, when setting of standard vehicle height is incomplete.
 If malfunction is detected, the syste m enters fail-safe mode. Refer to SCS-59, "
Fail-safe".
Vehicle Height SensorINFOID:0000000006256043
Measures vehicle height of vehicle rear and transmits th is information to air levelizer control module according
to electric signal.
Air CompressorINFOID:0000000006256044
Operates according to signal from air levelizer control module via air compressor relay, and charges air in air
chamber of rear shock absorber.
EXHAUST SOLENOID
Operates according to signal from air levelizer control module, and discharges air in air chamber of rear shock
absorber.
Air Compressor RelayINFOID:0000000006256045
Turns ON according to signal from air levelizer control module, and operates air compressor.
CK SUSP Indicator LampINFOID:0000000006256046
 Turns ON for 2 seconds when ignition switch is turned ON, for the purpose of bulb check.
 Turns ON when setting of standard vehicle height is incomplete.
NOTE:
Does not turn ON when the system is malfunctioning.
Air compressor relay SCS-51, "Air Compressor Relay"
CK SUSP indicator lampSCS-51, "CK SUSP Indicator Lamp"
Component parts Reference
Revision: 2010 May2011 QX56

SYSTEMSCS-55
< SYSTEM DESCRIPTION > [AIR LEVELIZER CONTROL SYSTEM]
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Vehicle height raises [When starting engi
ne, if vehicle height of vehicle rear continues for 30 seconds or more in a
status that is 15 mm (0.59 in) or less than standard vehicle height]
1. Vehicle height sensor detects vehicle height status, and transmits this information to air levelizer control
module.
2. Air levelizer control module turns air compressor relay ON and operates air compressor.
3. Air compressor charges air in air chamber of shock absorber.
4. Vehicle height raises, and control is complete when status is −1 mm ( −0.04 in) of standard vehicle height
value.
Vehicle height lowers [When starting engine, if vehicle height of vehicle rear continues for 30 seconds or more in a
status that is 15 mm (0.59 in) or more of standard vehicle height]
1. Vehicle height sensor detects vehicle height status, and transmits this information to air levelizer control
module.
2. Air levelizer control module turns exhaust solenoid of air compressor ON.
3. Air compressor discharges air from air chamber of shock absorber.
4. Vehicle height lowers, and control is complete when st atus is +1 mm (+0.04 in) of standard vehicle height.
Fail-safeINFOID:0000000006256051
If malfunction is detected, control stops.
The system may enter fail-safe mode under certain conditions (for example, over-laden conditions) when elec-
tronic circuit is normal.
In this case, always check that the system re turns to normal by starting engine after unloading load.
JSEIA0221GB
Revision: 2010 May2011 QX56

SCS-58
< ECU DIAGNOSIS INFORMATION >[AIR LEVELIZER CONTROL SYSTEM]
AIR LEVELIZER CONTROL MODULE
ECU DIAGNOSIS INFORMATION
AIR LEVELIZER CONTROL MODULE
Reference ValueINFOID:0000000006256053
VALUES ON DIAGNOSIS TOOL
TERMINAL LAYOUT
PHYSICAL VALUES
Item name Condition Value/Status (Approx.)
IGN VOLT Ignition switch ON 10 – 16 V
VHCL HT INTLZ STA Completion of the standard vehicle height setting CMPLT
Other than the above INCMP
VHCL HT INIT SLCT Completion of the standard vehicle height setting 1
Other than the above 0
VHCL HEIGHT SEN Lift up the vehicle 2.8 – 3.8 V
VHCL HT CNVSN VL Lift down the vehicle −15 – 15 mm
VHCL HGT FIX TIME Lift up the vehicle 0 h
VHCL HGT INIT VAL Completion of the standard vehicle height setting 2.800 – 3.800 V
Other than the above 0 V
COMPRESSOR When the air compressor is operating On
Other than the above Off
EXH SOLENOID When exhaust solenoid is operating On
Other than the above Off
ENG SPEED SIG Engine running RUN
Other than the above STOP
WARNING LAMP When CK SUSP indicator lamp is ON On
Other than the above Off
JSDIA0057ZZ
Terminal
(Wire color) Description
ConditionReference value
(Approx.)
+ − Signal name Input/
Output
2
(B) Ground GND — Always Less than 1
Ω
3
(V) Ground Air compressor relay Output IGN ON Air compressor: ON 9 – 16 V
Air compressor: OFF Less than 2 V
4
(L/W) Ground Vehicle height sensor
(GND) — Always Less than 1
Ω
Revision: 2010 May2011 QX56

AIR LEVELIZER CONTROL MODULESCS-59
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Fail-safeINFOID:0000000006256054
If malfunction is detected, control stops.
The system may enter fail-safe mode under certain condi tions (for example, over-laden conditions) when elec-
tronic circuit is normal.
In this case, always check that the system re turns to normal by starting engine after unloading load.
DTC Inspection Priority ChartINFOID:0000000006256055
If some DTCs are displayed at the same time, per form inspections one by one based on the following priority
chart.
DTC IndexINFOID:0000000006256056
5
(W) Ground Vehicle height sensor
(SIGNAL) InputIGN ON 0.2 – 4.6 V
IGN OFF 0 V
7
(P) 16
(L) CAN-L
Input/
Output — 54 – 69
Ω
9
(P/L) Ground Air levelizer co
ntrol module
power supply InputIGN ON 10 – 16 V
IGN OFF 0 V
11
(V/W) Ground Exhaust solenoid Output IGN ON Exhaust solenoid: ON 9 – 16 V
Exhaust solenoid: OFF Less than 2 V
13
(R) Ground Vehicle height sensor
(Power supply)
OutputIGN ON 4.5 – 5.5 V
IGN OFF 0 V
16
(L) 7
(P) CAN-H Input/
Output — 54 – 69
Ω
Te r m i n a l
(Wire color) Description
ConditionReference value
(Approx.)
+ − Signal name Input/
Output
Priority Detected items (DTC)
1  U1000 CAN COMM CIRCUIT
 U1010 CONTROL UNIT (CAN)
2  C1801 VHCL HEIGHT SENSOR
 C1802 AIR SUS COMPRS RELAY
 C1803 AIR SUS EXH SOL
 C1806 VHCL HEIGHT SEN FIX
 C1807 VHCL HEIGHT SEN VOLT
3  C1804 VHCL HEIGHT ADJ UP
 C1805 VHCL HEIGHT ADJ DOWN
 C1808 AIR SUS COMPRS FNCTN
DTC CONSULT-III display Reference page
C1801 VHCL HEIGHT SENSOR SCS-69
C1802 AIR SUS COMPRS RELAYSCS-72
C1803 AIR SUS EXH SOLSCS-74
C1804 VHCL HEIGHT ADJ UPSCS-77
C1805 VHCL HEIGHT ADJ DOWNSCS-80
C1806 VHCL HEIGHT SEN FIXSCS-81
C1807 VHCL HEIGHT SEN VOLTSCS-82
C1808 AIR SUS COMPRS FNCTNSCS-84
Revision: 2010 May2011 QX56

SCS-72
< DTC/CIRCUIT DIAGNOSIS >[AIR LEVELIZER CONTROL SYSTEM]
C1802 AIR SUS COMPRS RELAY
C1802 AIR SUS COMPRS RELAY
DTC LogicINFOID:0000000006256065
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If “DTC CONFIRMATION PROCEDURE” has been previous ly conducted, always turn ignition switch OFF
andwait at least 10 seconds before conducting the next test.
>> GO TO 2.
2.CHECK DTC DETECTION
With CONSULT-III
1. Turn ignition switch ON and wait 10 seconds or more.
2. Select “COMPRESSOR” in “Active Test” in “E-SUS”.
3. Touch “ON” and wait 5 seconds or more.
4. Select “Self Diagnostic Result” in “E-SUS”.
Is
“C1802” detected ?
YES >> Go to SCS-72, "DiagnosisProcedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006256066
1.CHECK AIR COMPRESSOR ON SIGNAL FROM AIR LEVELIZER CONTROL MODULE
CONSULT-III
1. Disconnect air compressor relay connector.
2. Turn ignition switch ON. CAUTION:
Never start the engine.
3. Select “COMPRESSOR” in “Active Test” in “E-SUS”.
4. Touch “ON”.
5. While operating test item, check voltage betw een air compressor relay harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 2.
2.CHECK HARNESS BETWEEN AIR LEVELIZER CO NTROL MODULE AND AIR COMPRESSOR RELAY
1. Turn ignition switch OFF.
2. Disconnect air levelizer control module connector.
DTC Display item Malfunction detected condition Possible cause
C1802 AIR SUS COMPRS RELAY  Output voltage of the air compressor relay remains
9 V or less continuously for 5 seconds during air
compressor ON signal output by the air levelizer
control module.
 Output voltage of the air compressor relay remains
2 V or more continuously for 10 seconds during air
compressor OFF signal output by the air levelizer
control module.  Harness or connector
 Air compressor relay
 Air levelizer control module
Air compressor relay
—Voltage
Connector Terminal
E116 2 Ground 9 – 16 V
Revision: 2010 May2011 QX56

C1802 AIR SUS COMPRS RELAYSCS-73
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3. Check continuity between air levelizer control module harness connector and air compressor relay har-
ness connector.
4. Check continuity between air levelizer control module harness connector and ground.
5. Check voltage between air levelizer control module harness connector and ground.
Are the inspection results normal?
YES >> GO TO 3.
NO >> Repair or replace damaged part.
3.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
Is the inspection result normal?
YES >> Replace the air levelizer control module. Refer to SCS-94, "Removal and Installation".
NO >> Repair or replace damaged parts.
4.CHECK AIR COMPRESSOR RELAY GROUND
1. Turn ignition switch OFF.
2. Check continuity between air compressor relay harness connector and ground.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace damaged part.
5.CHECK AIR COMPRESSOR RELAY
1. Remove the air compressor relay. Refer to SCS-50, "
Component Parts Location".
2. Check continuity between air compressor relay harness connector terminals.
Is the inspection result normal?
YES >> Check intermittent incident. Refer to GI-40, "Intermittent Incident".
NO >> Replace the air compressor relay. Refer to SCS-50, "
Component Parts Location".
Air levelizer control module Air compressor relay
Continuity
Connector Terminal Connector Terminal
B84 3 E116 2 Existed
Air levelizer control module
—Continuity
Connector Terminal
B84 3 Ground Not existed
Air levelizer control module
—Voltage
Connector Terminal
B84 3 Ground 0 V
Air compressor relay —Continuity
Connector Terminal
E116 1 Ground Existed
Air compressor relay Continuity
Te r m i n a l
12Existed
Revision: 2010 May2011 QX56

C1804 VHCL HEIGHT ADJ UPSCS-77
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C1804 VHCL HEIGHT ADJ UP
DTC LogicINFOID:0000000006256070
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If “DTC CONFIRMATION PROCEDURE” has been previous ly conducted, always turn ignition switch OFF
andwait at least 10 seconds before conducting the next test.
>> GO TO 2.
2.CHECK DTC DETECTION
With CONSULT-III
1. Set vehicle in the unloaded vehicle status.
2. Start the engine and wait 150 seconds or more.
3. Perform “Self Diagnostic Result” in “E-SUS”.
Is
“C1804” detected ?
YES >> Go to SCS-77, "DiagnosisProcedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006256071
1.CHECK APPEARANCE
Visually check for malfunction of suspension component s, damage of air chamber of rear shock absorber,
installation malfunction, or defo rmation of vehicle height sensor.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repaire or replace damaged parts.
2.CHECK AIR LEAK
Apply soapy water to air tube, connecting portions between air tube and each component, and air chamber of
rear shock absorber. Check for air leakage.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repaire or replace damaged parts.
3.CHECK AIR COMPRESSOR RELAY POWER SUPPLY
1. Turn ignition switch OFF.
2. Check 30A fuse (#I).
3. Disconnect air compressor relay connector.
4. Check voltage between air compressor relay harness connector and ground.
DTC Display item Malfunction detected condition Possible cause
C1804 VHCL HEIGHT ADJ UP The vehicle height is 15 mm (0.59 in) or more lower
than the reference height despite the output of air
compressor ON signal continuously for 120 seconds
by the air levelizer control module.  Harness or connector
Air compressor
 Air compressor relay
 Air levelizer control module
 Rear shock absorber (air cham-
ber)
 Vehicle height sensor
 Air tube
 Rear suspension component parts
 Overloaded
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SCS-78
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C1804 VHCL HEIGHT ADJ UP
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace damaged part.
4.CHECK AIR COMPRESSOR
RELAY OUTPUT CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect air compressor connector.
3. Check continuity between air compressor relay harness connector and air compressor harness connector.
4. Check continuity between air compressor relay harness connector and ground.
Are the inspection results normal?
YES >> GO TO 5.
NO >> Repair or replace damaged part.
5.CHECK AIR COMPRESSOR GROUND
Check continuity between air compressor harness connector and ground.
Are the inspection results normal?
YES >> GO TO 6.
NO >> Repair or replace damaged part.
6.CHECK AIR COMPRESSOR RELAY
Check the air compressor relay. Refer to SCS-79, "
Component Inspection (Air Compressor Relay)".
Is the inspection result normal?
YES >> GO TO 7.
NO >> Replace the air compressor relay.
7.CHECK AIR COMPRESSOR
Check the air compressor. Refer to SCS-79, "
Component Inspection (Air Compressor)".
Is the inspection result normal?
YES >> GO TO 8.
NO >> Replace the air compressor. Refer to SCS-95, "
Removal and Installation".
8.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
Is the inspection result normal?
YES >> 1. Perform “STANDARD VEHICLE HEIGHT SETTING”. Refer to SCS-67, "Work Procedure".
2. If DTC is detected, replace the air levelizer control module. Refer to SCS-94, "
Removal and
Installation".
Air compressor relay
—Voltage
Connector Terminal
E116 5 Ground Battery voltage
Air compressor rela y Air compressor
Continuity
Connector Terminal Connector Terminal
E116 3 C12 1 Existed
Air compressor relay —Continuity
Connector Terminal
E116 3 Ground Not existed
Air compressor —Continuity
Connector Terminal
C12 2 Ground Existed
Revision: 2010 May2011 QX56