RF-34
< ECU DIAGNOSIS >
SUNROOF SYSTEM
Wiring Diagram
INFOID:0000000005147294
ABKWA0520GB
Revision: April 20092010 QX56
SCS-1
SUSPENSION
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SECTION SCS
A
B
SCS
N
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 ...............23
Description ...............................................................23
Component Function Check ....................................23
Diagnosis Procedure ...............................................23
Revision: April 20092010 QX56
SCS-2
EXHAUST VALVE SOLENOID CIRCUIT ..........24
Description ........................................................... ...24
Component Function Check ...................................24
Diagnosis Procedure ..............................................24
CK SUSP WARNING INDICATOR CONTROL
CIRCUIT .............................................................
26
Description ........................................................... ...26
Component Function Check ...................................26
Diagnosis Procedure ..............................................26
ECU DIAGNOSIS ..................................... ...28
SUSPENSION CONTROL UNIT ........................28
Reference Value .................................................. ...28
Wiring Diagram .......................................................29
DTC Index ..............................................................34
SYMPTOM DIAGNOSIS .............................36
SUSPENSION CONTROL SYSTEM .............. ...36
Symptom Table ................................................... ...36
SUSPENSION CONTROL SYSTEM INOPER-
ATIVE .................................................................
37
Description ........................................................... ...37
Diagnosis Procedure ...............................................37
SUSPENSION CONTROL SYSTEM DOES
NOT RAISE ........................................................
38
Description ........................................................... ...38
Diagnosis Procedure ...............................................38
SUSPENSION CONTROL SYSTEM DOES
NOT LOWER .....................................................
39
Description ........................................................... ...39
Diagnosis Procedure ...............................................39
PRECAUTION ............................................40
PRECAUTIONS .............................................. ...40
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" .............................................................. ...
40
Precaution for Rear Suspension .............................40
Revision: April 20092010 QX56
SUSPENSION CONTROL SYSTEMSCS-5
< FUNCTION DIAGNOSIS >
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SCS
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FUNCTION DIAGNOSIS
SUSPENSION CONTROL SYSTEM
System DiagramINFOID:0000000005148146
System DescriptionINFOID:0000000005148147
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: April 20092010 QX56
C1807 SENSOR 5V MALFUNCTIONSCS-15
< COMPONENT DIAGNOSIS >
C
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M A
B
SCS
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C1807 SENSOR 5V MALFUNCTION
DescriptionINFOID:0000000005148169
The vehicle height sensor operates on a 5 volt referenc e signal from the suspension control unit. The suspen-
sion control unit also provides ground to the height sensor.
DTC LogicINFOID:0000000005148170
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000005148171
Regarding Wiring Diagram information, refer to SCS-29, "Wiring Diagram".
1.POWER SUPPLY CIRCUIT CHECK
1. Disconnect height sensor connector C8.
2. Turn the ignition switch ON.
3. Check voltage between the height sensor connector C8 terminal 1 and ground.
Is 5V present?
YES >> System is working normally.
NO >> Check harness or connector for open or short. If OK, replace the suspension control unit. Refer to RSU-26, "
Removal and Installation".
DTC CONSULT-IIIDiagnostic item is detected when ... Probable malfunction location
C1807 SENSOR 5V MALFUNC-
TION Sensor reference voltage is less than 0.8V or
more than 6V for 20 seconds. • Height sensor power/ground supply. Refer to
SCS-18, "
HEIGHT SENSOR : Diagnosis
Procedure".
• Charging system malfunction. Refer to CHG-
8, "Inspection Procedure".
(+)
(-) Voltage
Connector Terminal
C8 1 Ground 5V
ALEIA0026GB
Revision: April 20092010 QX56
POWER SUPPLY AND GROUND CIRCUITSCS-17
< COMPONENT DIAGNOSIS >
C
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G H
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M A
B
SCS
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POWER SUPPLY AND GROUND CIRCUIT
SUSPENSION CONTROL UNIT
SUSPENSION CONTROL UNIT : Diagnosis ProcedureINFOID:0000000005148175
Regarding Wiring Diagram information, refer to SCS-29, "Wiring Diagram".
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:0000000005148176
Regarding Wiring Diagram information, refer to SCS-29, "Wiring Diagram".
UnitTerminals Signal name Fuse No.
Suspension control unit 7
Battery power 29
6 Ignition switch ON or START 12
(+)
(-) OFF ACC ON
Connector Terminal
B3 7Ground
Battery
voltage Battery
voltage Battery
voltage
6Ground0V 0V Battery
voltage
AWEIA0114ZZ
Connector Terminal —Continuity
B3 16Ground Yes
ALEIA0028GB
Revision: April 20092010 QX56
SCS-18
< COMPONENT DIAGNOSIS >
POWER SUPPLY AND GROUND CIRCUIT
1.CHECK COMPRESSOR MOTOR RELAY OPRATION
CONSULT-III
1. Disconnect the suspension air compressor connector C9.
2. Turn ignition switch ON.
3. Select "COMPRESSOR" under AIR LEVELIZER active test items.
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:0000000005148177
Regarding Wiring Diagram information, refer to SCS-29, "Wiring Diagram".
(+)
(-)Voltage
Connector Terminal
C9 4Ground Battery Voltage
ALEIA0021GB
AB
Continuity
Connector Terminal Connector Terminal
E131 3 C9 4 Yes
A —Continuity
Connector Terminal
E131 3Ground No
ALEIA0022GB
Connector Terminal —Continuity
C9 1
Ground Yes
3
ALEIA0023GB
Revision: April 20092010 QX56
SCS-20
< COMPONENT DIAGNOSIS >
COMPRESSOR MOTOR RELAY
COMPRESSOR MOTOR RELAY
DescriptionINFOID:0000000005148178
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:0000000005148179
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:0000000005148180
Regarding Wiring Diagram information, refer to SCS-29, "Wiring Diagram".
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 ON : Compressor turns ON
OFF : Compressor turns OFF
(+)
(-)Voltage
Connector Terminal
E130 2Ground Battery voltage
ALEIA0030GB
Revision: April 20092010 QX56