1989 MITSUBISHI GALANT Service Repair Manual

33B-70 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[25]LEFT FRONT/RIGHT FRONT VALVE ACTIVATION CIRCUIT
Front solenoid valve assembly
(Cowl top panel center) Front
“/irontexhaust
valve air springs
12A0370
Usually. and
during exhaust. Front
OFF (closed)
- ;;,PPlY
Left front
Front and right
exhaust
--front ai
r
valve springs
12AO264
Riaht front
Left front valvevaive
Fron
air-supply
valve
4
12AO490
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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-71
Operation
The left front and right front valves are for switching
the air intake and exhaust for the left front and right
front strut air springs. These valves are usually,
Diagnostic and during air intake, OFF (closed), and are ON
(open) during exhaust.
If there is damage or disconnection of the heavy-line control is as described in the table below.
circuit, or a malfunction of an output transistor Note that the malfunction-detection circuit is the
within the ECU, the alarm light illuminates, and same for the left front and right front valves.
Diagnostic No.
52
Damping forceVehicle-herghtSwitch acceptance
Attitude control controlcontrol
HIGH
SPORT AUTOSOFT
Control stop
Held at MEDIUM Control stop Not accept
Actuator compulsory activation
The left front and right front valves are activated by
the following.
Code No. Applicable operation
07Vehicle height aownward adjustment
09.10 Rolling control (left turning: left
valve)/rollingcontrol (rrght turning: right valve)
ECU terminal voltages (when connector is connected] Termrnal
No
Slgnal
ConditionTerminal
voltage
3Left front valve activatron
When the left/right front valves are ONB+srgnal~ When the left/right front valves are OFF o
v
4Right front valve
activatronsrgnalDuring fail-safe (for solenoid valve power source relay switch OFF)
o
v
B+: Battery positive voltage
Checking the left front/right front valves activation circuit (with the\
connector disconnected)
I No. Terminal
Connection destination or
Measurement
Imeasured part Tester connection
Check conditionStandard
3Left front valve Resrstance3-groundConstantly
Approx 1012
4Right front valve
Resistance4-groundConstantly Approx 1012
Troubleshooting hints (mechanical malfunctions)Malfunctron
mode
Stuck
In the
OFF (closed)
position
Stuck
In the
ON (open) oositron
Air leakage at valve seat
Air leakage tc
atmosphere
!
Malfunction probable cause Malfunction
NoteAir
cannot be discharged because
l-
the valve is stuck in the OFF (closed) The left front and right front vehicle height
due to corrosion, freezing, etc. increases after rolling control.0Insufficient active control effect.
caused by moisture penetration.
Air cannot be taken in because the
lvalve is stuck in the ON (open) due The left front and right front vehicle height
Diagnostic trouble
decreases, and the body tilts to one side.
to corrosion. freezing, etc. caused code No.56 is output.lThe return pump is activated too frequently.
by moisture penetration
Valve seat is worn
W
ear, etc of the O-ring, etc
When left as is, the front vehicle-height will
decrease. Diagnostic trouble
code No.56 is output.
When left as is. the front vehicle-height will decrease.
Very slight leakages can-not be detected. Such
leakage IS detected a longtime afterward by a decre- ase of the vehicle height
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33B-72 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[26] LEFT REAR/RIGHT REAR VALVE ACTIVATION CIRCUIT
tear solenoid valve assemblyLuggagecompartmentright front surface)Rear (riaht)
Rear (left)
valve
Rearair-supply
valve
Rear exhaust valve springs
12A0371Usually, and
during exhaust,
OFF (closed)
Rearc- air-supply
valve
Rearexhaust -
Left rear/right- rear air springs
valve
12A0264
040A Subfwblehnk
l-l-7
015A
Relay box
C-06
~~oL&~~ , 2J$$i ECU
F~‘7
IIY *- - _..
m1 2
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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-73
Operation
The left rear and right rear valves are for switching
the air supply and exhaust for the left rear and right rear shock absorber air springs. These valves are
Diagnostic usually, and during air supply, OFF (closed), and are
ON (open) during exhaust.
If there is damage or disconnection of the heavy-line
circuit, or a malfunction of an output transistor
within the ECU, the alarm light illuminates, and control is as described in the table below.
Note that the malfunction-detection circuit is the
same for the left rear and right rear valves.
Diagnostic No.
53
Damping force Vehicle-height Switch acceptance
Attitude control controlcontrol
HIGHSPORTAUTOSOFT
Control stop
Held at MEDIUMControl stop Not accept
Actuator compulsory activation
The left rear and right rear valves are activated by
the following.
Code No. Applicable operation
I07/ Vehicle height downward adjustmentI
09.1
0
Rolling control (left turning, left
valve)/rollingcontrol (right
turning: right valve)
ECU terminal voltages (when connector is connected) Terminal
No.Signal ConditionTerminal
voltage
29 Left rear valve activation When the left/right rear valves are ON
signal
E3a3azg~ positive
~ When the left/right rear valves are OFF o
v
27 Right rear valve activation
signal During fail-safe (for solenoid valve power source relay switch OFF) ov
Checking the left rear/right rear valves activation circuit (with
the connector disconnected)
Terminal Connection destination or
MeasurementNo.measured part Tester connection
29 Left rear valve Resistance
29-ground
27Right rear valve
Resistance27-ground
Troubleshooting hints (mechanical malfunctions) Check condition
Constantly
Constantly Standard
Approx
1011
Approx. 1 Of2
Malfunction mode Malfunction probable cause
IMalfunction
Note
Stuck in the
OFF (closed)
position
Stuck in the
ON (open)
position
Air leakage
at valve seat
Air leakage
tcatmosphere Air cannot be discharged because
l
The left rear and right rear vehicle height
the valve is stuck in the OFF (closed)
increases after rolling control.
due to corrosion, freezing, etc. 0
Insufficient active control effect.
caused by moisture penetration.
Air cannot be taken in because the
lThe left rear and right rear vehicle height
valve is stuck in the ON (open) due decreases, and the body tilts to one side.
to corrosion, freezing, etc caused l
The return pump is activated too frequently
by moisture penetration.
Valve seat is worn. When left as is, the rear vehicle-height will decrease.
W
ear, etc. of the O-ring, etc.
When left as is, the rear vehicle-height will decrease.
TSB Revision Diagnostic trouble
code
No.56 is output
Diagnostic trouble
code
No.56 is output
Very slight leakages can- not be detected. Such
leakage is detected a long
time afterward by a decre- ase of the vehicle height.

33B-74 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting[27]
ACTIVE-ECS RELATED DIAGNOSTIC/SERVICE DATA OUTPUT CIRCUIT
ECU
IGz
8’i- 1
F-19
F-16
mi
_-___- ____79
-I I
58 E
0
___--
1
_-___---
g7
3
.-
13
t
r
16131817\I/ (1989
models)
Vehicle-speed
sensor (meter) c-43
Serial/on-board
diagnostic outputconnector
C-l 8
p!5iE&qSimulatedvehicle-
-1
speed
input
12AO479
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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-75
ECU terminal voltages (when connector is connected)
TerminalNo.Condition
Terminal
voltage
79 Diagnostic/service data
switching signal When scan tool is connected
Usual
o
v
3.3v
84
Diagnostic/service data
switching signal ConstantlyO;JBattery posi-
tive voltage
ACTIVE-ECS related diagnostic/service data output circuit (with the con\
nector disconnected) Terminal Connection destination or
MeasurementNo.measured part Tester connection
Check condition
Standard
79 Diagnostic/service
data switching signal Resistance
Diagnostic
79- concentrated
connector ~
Constantly Continuity
84 Harness for
diagnostic/service
data output Resistance
Diagnostic
84- concentrated
connector Constantly
Continuity
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33B-76 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
CONFIGURATION DIAGRAMS ENGINE ROOM
A-l 1 A-12 A-54
A-28
A-27
2:;. Refer to CENTRALIZED JUNCTIONIA-l 1ACTIVE-ECS exhaust solenoid valve
A-l 2 ACTIVE-ECS air compressor A-23
ACTIVE-ECS
G sensor A-27 ACTIVE-ECS front vehicle height sensor
A-28
ACTIVE-ECS flow-control solenoid valve A-37
ACTIVE-ECS return pump A-38
ACTIVE-ECS pressure switch A-39
ACTIVE-ECS air compressor relay
A40 ACTIVE-ECS return pump relayA-41 Front wiring harness and battery
cable combination A-50
ACTIVE-ECS front actuator A-54
Throttle position sensor (1989 models) A-58
ACTIVE-ECS front solenoid valve A-63
ACTIVE-ECS front actuator
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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-77
A-58A-63
-.__- --~- ~---~
111111111
Ground point (detailed view)
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