sensor INFINITI QX56 2010 Factory Service Manual

SUSPENSION CONTROL SYSTEMSCS-5
< FUNCTION DIAGNOSIS >
C
DF
G H
I
J
K L
M A
B
SCS
N
O P
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

SCS-6
< FUNCTION DIAGNOSIS >
SUSPENSION CONTROL SYSTEM
Component Parts Location
INFOID:0000000005148148
:Front
Component DescriptionINFOID:0000000005148149
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: April 20092010 QX56

C1801 VEHICLE HEIGHT SENSORSCS-9
< COMPONENT DIAGNOSIS >
C
DF
G H
I
J
K L
M A
B
SCS
N
O P
COMPONENT DIAGNOSIS
C1801 VEHICLE HEIGHT SENSOR
DescriptionINFOID:0000000005148151
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. Depending on vehicle height, the height sensor
signal should have between 0.2V and 4.8V.
DTC LogicINFOID:0000000005148152
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000005148153
1.CHECK HEIGHT SENSOR OPERATION
CONSULT-III
1. Turn ignition switch ON
2. Select "HEIGT SEN" of AIR L EVELIZER data monitor test item.
Is the HEIGHT SEN voltage within the given range?
YES >> Height sensor is operating normally.
NO >> Refer to SCS-23, "
Diagnosis Procedure".
DTC CONSULT-III Diagnostic item is detected when ... Probable malfunction location
C1801 VEHICLE HEIGHT SEN-
SOR Vehicle height sensor voltage is less than 0.2V
or greater than 4.8V for more than 60 seconds. • Height sensor power/ground supply. Refer to
SCS-18, "
HEIGHT SENSOR : Diagnosis
Procedure".
• Height sensor signal circuit. Refer to SCS-
23, "Component Function Check".
HEIGHT SEN : 0.2V - 4.8V
Revision: April 20092010 QX56

SCS-14
< COMPONENT DIAGNOSIS >
C1806 VEHICLE HEIGHT SENSOR LOCKING MALFUNCTION
C1806 VEHICLE HEIGHT SENSOR LOCKING MALFUNCTION
DescriptionINFOID:0000000005148166
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:0000000005148167
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000005148168
1.CHECK HEIGHT SENSOR OPERATION
CONSULT-III
1. Turn ignition switch ON
2. Select "HEIGT SEN" of AIR LEVELIZER data monitor test item.
Is the HEIGHT SEN voltage within the given range?
YES >> Height sensor is operating normally.
NO >> Refer to SCS-23, "
Diagnosis Procedure".
DTC CONSULT-III Diagnostic item is detected when ... Probable malfunction location
C1806 VEHICLE HEIGHT SEN-
SOR LOCKING MAL-
FUNCTION Output sensor voltage variation
±0.02V is more
than 100 seconds when vehicle height range is
normal. • Height sensor power/ground supply. Refer to
SCS-18, "
HEIGHT SENSOR : Diagnosis
Procedure".
• Charging system malfunction. Refer to CHG-
8, "Inspection Procedure".
HEIGHT SEN : 0.2V - 4.8V with no more than ± 0.02V
variation
Revision: April 20092010 QX56

C1807 SENSOR 5V MALFUNCTIONSCS-15
< COMPONENT DIAGNOSIS >
C
DF
G H
I
J
K L
M A
B
SCS
N
O P
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

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

POWER SUPPLY AND GROUND CIRCUITSCS-19
< COMPONENT DIAGNOSIS >
C
DF
G H
I
J
K L
M A
B
SCS
N
O P
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 >> GO TO 2.
NO >> Check harness or connector for open or short. If OK, replace the suspension control unit. Refer to RSU-26, "
Removal and Installation".
2.GROUND CIRCUIT CHECK
1. Turn ignition switch OFF.
2. Check continuity between height sensor connector C8 terminal 3 and ground.
Is continuity present?
YES >> Ground circuit is OK.
NO >> Repair harness or connector.
(+) (-) Voltage
Connector Terminal
C8 1 Ground 5V
ALEIA0026GB
Connector Terminal —Continuity
C8 3Ground Yes
ALEIA0029GB
Revision: April 20092010 QX56

HEIGHT SENSOR SIGNAL CIRCUITSCS-23
< COMPONENT DIAGNOSIS >
C
DF
G H
I
J
K L
M A
B
SCS
N
O P
HEIGHT SENSOR SIGNAL CIRCUIT
DescriptionINFOID:0000000005148181
Supplies vehicle height input to the suspension control unit.
Component Function CheckINFOID:0000000005148182
1.CHECK HEIGHT SENSOR OPERATION
CONSULT-III
1. Select "HEIGT SEN" of AIR L EVELIZER data monitor test item.
2. While monitoring test item, add or take away weight from the rear of the vehicle. Check that the voltage value changes with vehicle height.
Is the HEIGHT SEN data monitor responding normally?
YES >> Height sensor is operating normally.
NO >> Refer to SCS-23, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000005148183
Regarding Wiring Diagram information, refer to SCS-29, "Wiring Diagram".
1.CHECK HEIGHT SENSOR POWER AND GROUND SUPPLY
Check height sensor power and ground supply. Refer to SCS-18, "
HEIGHT SENSOR : Diagnosis Procedure".
Are the inspection results normal?
YES >> GO TO 2.
NO >> Repair harness or connector.
2.CHECK HEIGHT SENSOR SIGNAL CIRCUIT
1. Disconnect suspension control unit connector B3 and height sensor connector C8.
2. Check continuity between suspension control unit connector B3
(A) terminal 3 and height sensor connector C8 (B) terminal 2.
3. Check continuity between display unit harness connector B3 (A) terminal 3 and ground.
Are the continuity results as specified?
YES >> Replace the height sensor. Refer to RSU-27, "Removal and Installation".
NO >> Repair harness or connector. HEIGHT SEN : Voltage changes with vehicle height
AB
Continuity
Connector Terminal Connector Terminal
B33C 82 Y es
A —Contin u it y
Connector Terminal
B3 3Ground No
ALEIA0035GB
Revision: April 20092010 QX56

SCS-28
< ECU DIAGNOSIS >
SUSPENSION CONTROL UNIT
ECU DIAGNOSIS
SUSPENSION CONTROL UNIT
Reference ValueINFOID:0000000005148190
TERMINAL LAYOUT
PHYSICAL VALUES
AWLIA1640ZZ
Terminal
(Wire color) Description
ConditionReference value
(Approx.)
+ – Signal nameInput/
Output
1
(V) Ground Compressor relay output Output Ignition
switch ON Air levelizer raising vehicle
ride height
Battery voltage
3
(W) Ground Height sensor input
InputIgnition
switch
ON —0
.2 V - 4 .8 V
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 lowering 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: April 20092010 QX56

SCS-34
< ECU DIAGNOSIS >
SUSPENSION CONTROL UNIT
DTC Index
INFOID:0000000005148192
Self-diagnosis results display item
ABEIA0018GB
CONSULT-III display MalfunctionReference page
Vehicle height sensor [C1801] Vehicle height sensor voltage is less than 0.2V or greater than
4.8V for more than 60 seconds. SCS-9,
"DiagnosisProcedure".
Revision: April 20092010 QX56