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SCS-28
< ECU DIAGNOSIS >
SUSPENSION CONTROL UNIT
Wiring Diagram
INFOID:0000000003772352
ABEWA0006GB
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SUSPENSION CONTROL UNITSCS-29
< ECU DIAGNOSIS >
C
DF
G H
I
J
K L
M A
B
SCS
N
O P
ABEIA0014GB
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SCS-30
< ECU DIAGNOSIS >
SUSPENSION CONTROL UNIT
ABEIA0015GB
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SUSPENSION CONTROL UNITSCS-31
< ECU DIAGNOSIS >
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M A
B
SCS
N
O P
ABEIA0016GB
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SCS-32
< ECU DIAGNOSIS >
SUSPENSION CONTROL UNIT
ABEIA0017GB
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SUSPENSION CONTROL UNITSCS-33
< ECU DIAGNOSIS >
C
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M A
B
SCS
N
O P
DTC IndexINFOID:0000000003772353
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".
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![INFINITI QX56 2009 Factory Service Manual SCS-34
< ECU DIAGNOSIS >
SUSPENSION CONTROL UNIT
Compressor relay [C1802]• Driving transistor for compre
ssor relay is OFF and monitor
voltage continues at a high level for more than 10 seconds.
INFINITI QX56 2009 Factory Service Manual SCS-34
< ECU DIAGNOSIS >
SUSPENSION CONTROL UNIT
Compressor relay [C1802]• Driving transistor for compre
ssor relay is OFF and monitor
voltage continues at a high level for more than 10 seconds.](/manual-img/42/57031/w960_57031-3226.png)
SCS-34
< ECU DIAGNOSIS >
SUSPENSION CONTROL UNIT
Compressor relay [C1802]• Driving transistor for compre
ssor relay is OFF and monitor
voltage continues at a high level for more than 10 seconds.
• Driving transistor for compre ssor relay is ON and monitor
voltage continues at a low level for more than 5 seconds. SCS-10, "DiagnosisProcedure".
Exhaust solenoid [C1803] • Driving transistor for exhaust valve solenoid is OFF and
monitor voltage continues at a high level for more than 10
seconds.
• Driving transistor for exhaust valve solenoid is ON and mon- itor voltage continues at a low level for more than 5 seconds. SCS-11,
"DiagnosisProcedure".
Vehicle height adjusting malfunc-
tion (compressor)[C1804] Continuous compressor relay ON time is more than 120 sec-
onds. SCS-12,
"DiagnosisProcedure".
Vehicle height adjusting malfunc-
tion (exhaust solenoid)[C1805] Continuous exhaust valve solenoid ON time is more than 120
seconds. SCS-13,
"DiagnosisProcedure".
Vehicle height sensor locking mal-
function [C1806] Output sensor voltage variation
±0.02V is more than 100 sec-
onds when vehicle height range is normal. SCS-14, "
Diagnosis Proce-
dure".
Sensor 5V malfunction [C1807] Sensor reference voltage is less than 0.8V or more than 6V for
20 seconds. SCS-15,
"DiagnosisProcedure"
Integral time malfunction by sup-
plying air [C1808]A suspension air compressor ON request has been in effect
for 180 seconds and the suspension air compressor has not
activated during that time. SCS-16,
"DiagnosisProcedure".
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SUSPENSION CONTROL SYSTEMSCS-35
< SYMPTOM DIAGNOSIS >
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SYMPTOM DIAGNOSIS
SUSPENSION CONTROL SYSTEM
Symptom TableINFOID:0000000003772354
AIR LEVELIZER
Symptom Possible causeReference page
Inoperative • Suspension control unit
• Compressor motor relay
• Suspension air compressorSCS-36, "
Diagnosis Proce-
dure"
System does not raise • Suspension control unit
• Height sensor
• Compressor motor relay
• Suspension air compressor
• Leak in system
• Restriction in systemSCS-37, "Diagnosis Proce-
dure"
System does not lower
• Suspension control unit
• Height sensor
• Compressor motor relay
• Suspension air compressor
• Restriction in systemSCS-38, "Diagnosis Proce-
dure"
CK SUSP indicator lamp always ON with key ON
• CK SUSP indicator lamp control circuit
• Suspension control unitSCS-25, "Description"
Revision: December 20092009 QX56