MITSUBISHI GALANT 1989 Service Repair Manual

33B-22 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[l] G-SENSOR CIRCUIT
112A0462
A-23
G-sensor output characteristic
Output voltage (VIRight- Left
IDirection of acceleration
-48.6" -30"
0’ 3P48.6"
LH --RH
Accelera-tion (G)Angle (D)[(A) surfacestandard]
G sensor
C-06
-1
F-l 8
[jiiEB%]
.8_-----
14
ECU
M
713_----
M
0
m
7835
1
standard
surface (A)- 12A0494
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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-23
Operation
The G-sensor detects the amount of acceleration
that is generated (to the left or right) when the
vehi-
response to acceleration, and these changes are
cle body turns. Applying the principle of the dif-
taken out as changes of voltage. Within the coil,
ferential transformer, the magnetic field changes silicon oil is enclosed in order to suppress the vibra-
tion of the movable iron core. Note that the
G-sen-
when the movable iron core within the coil moves in
Diagnostic sor is a special sensor for control of rolling.
When signals that are otherwise virtually
in-
conceivable are input due to damaged or discon-
a heavy-line circuit, the alarm light illuminates and
control is as described in the table below.
netted wiring or a short-circuit or similar problem of
Diagnostic No.Attitude controlDamplng force
controlVehicle-heightcontrol Switch acceptanceHIGH
SPORT AUTO SOFT
I11Rolling control
only stops Normal operation
Normal operation Accept
Service data indication
Code NoIndication
Standard value Display
11G-sensor output voltage 2.5V
when vehicle is horizontal 11: G SNSR:
2.5V
ECU terminal voltages (when connector is connected)
Terminal
NoCondition
Terminal
voltageIII
34 Power supply for sensor When the ECU is activated7.3vI
28G-sensor output signal
35 Sensor circuit earth When stoppedi
When wiring is damaged or disconnected
Constantly 2.5V
ov
ov
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-.
Checking the G-sensor circuit (with the connector disconnected)
Terminal ConnectIon
destination or MeasurementNomeasured part Tester connection
Check conditionStandard
28 G-sensor output
Resistance
28-2ConstantlyContinuity
34G-sensor power source
Resistance34-1ConstantlyContinuity
Troubleshooting hints
Malfunction
mode Malfunction probable causeMatfunctIonNoteSilicon
oil leakage
Because the sillcon
oil for
suppresslon of
l Rolling control occurs frequently-
vlbratlons of the G-sensor movable iron core is leaktng due to a collision.
the sensitivity is
oversensitive.
Damaged or
disconnected
earth line The ground line is damaged or disconnected.
l-Malfunction is not detected because the There are times of a feeling of
ground line is grounded to the G sensor’s body incompatibility of the rolling control
l
itself, however, noise is easily picked up. Rolling
control occurs suddenly; an error
occurs

33B-24 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[2]GENERATOR ‘I” TERMINAL CIRCUIT
rminal
12AO385
BatteryECUItI1
Main1OOA
fusible0hk
*33>
&CAI
2
I
I\//\/Relay
box
I
(1989 models)
I1TGENERATOR %
NOTE* mark is applicable for 1990, 1991, 1992, 1993 models.
B-16
C-23
[Isl:j
(From 1990 models)
12AQ496
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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-25
OperationThe generator
‘I-” terminal signal is used to deter-
pressor
operation, and is because activation of the
mine whether or not the engine is operating.
This is in order to reduce the frequency of
com-
system is possible while the engine is operating, or
at a vehicle speed of 3 km/h (2 mph) or higher.
Diagnostic
When the generator “L” terminal is LOW level (as a result of a short-circuit of the heavy-line circuit or
due to an abnormal condition of the generator) even
though the vehicle speed is 40 km/h (25 mph),
con-
trol is as described in the table below.Note,
however, that there is no detection if there is
damaged or disconnected wiring of the harness,
and the alarm light does not illuminate.
Diagnostic No. Attitude control Damping force
control Vehrcle-height
control
HIGH
Switch acceptance
SPORTAUTOSOFT
I12‘“L” terminal “L” logic
““L” terminal “L” logic: As a result of system operation conditions, the system is not ac\
tivated at a vehicle speed of less than 3 km/h (2mph). When the vehicle speed becomes 3 km/h (2 mph) or higher all fun\
ctions are normal. (Refer to the explanation of the opera-
tron.)
Service data indication
1 CodeNo. /Indication Display
I12The output voltage level of the12: ALT. LTERMI.
HIGH/LOW
generator “L” terminal is indicated.
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ECU terminal voltage (when connector is connected)
Terminal
No.Signal Condition Termrnal
voltage
52Generator ‘I” terminal signal When engine stalls
When engine is operating
When harness wiring is damaged or disconnected0.5-3v
13-15v
5v
Checking the generator “L” terminal circuit (with the connector d\
isconnected)
Terminal Connection destination or
M
easurement
No.measured part Tester connectronCheck condrtion
Standard
52 Generator
Voltage52 ground Ignition switch ON
2-5V
While engine is operatingB+
B+: Battery positive voltage

33B-26 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[3] LOW-PRESSURE SWITCH CIRCUIT
Low-pressure
switch
/ L>w-pressure
switch High-pressure

switch12AO172
o:t- -__-__-_--70 (10)140 (20)
Pressure kPa (psi)
12AO461
fwLow-pressure tankpressure detectlon
Low-pressure
switch
5 A-3812440492
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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-27
Operation
The low-pressure switch is switched ON and OFFby the pressure in the low-pressure tank, and as a becomes 140 kPa (20 psi) or higher, it is switched *
result the ECU functions to control the activation
OFF, and as a result the ECU sends the drive signal
and stop of the return pump. to the return pump. It is switched ON at a pressure
When the pressure in the low-pressure tank of 70
kPa (10 psi) or lower, and the return pump
stops two seconds later.
Diagnostic
If there is a short-circuit, or damaged or discon-
netted wiring, of the heavy-line
circuit,
or if the
low-pressure switch becomes shorted, and the low-pressure switch is as a result always ON, (the
trol)“, and control is as described in the table below.
alarm light illuminates during active attitude
con-
*: Information in () is applicable to 1989 models.
Not applicable to 1990 models.
Diagnostic No.Attitude control Damping force
Vehicle-height Switch acceptance
control controlHIGH
SPORTAUTOSOFT
13Control stop Normal operationNormal operation Accept
Service data indication
Code No.lndicatron
Display
13Indicates
ON or OFF condition of
13: LOW PRESS. SW. ON/OFF
the low-pressure switch
ECU terminal voltages (when connector is connected)
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/ Te;;,nal 1Condition Terminal
voltage
Low-pressure tank pressure
signalWhen the low-pressure switch is ONov
When the low-pressure switch is OFF5v
Checking the low-pressure switch circuit [with the connector disconnecte\
d).
I No.
Terminal Connection destination Measurement
!or measured partTester connectionCheck conditionStandard
38Low-pressure switch Resistance
38-36Low-pressure tank internalContinuit
y
pressure 70 kPa (10 psi) or
below
Low-pressure tank internalNo
pressure 140 kPa (20 psi) orcontinuity
higher.

33B-28 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[4] THROll-LE-POSITION SENSOR CIRCUIT
(1989 models)
(From 1990 models) A-54
+@7jg
(From 1990 models)
Throttle-position sensor output characteristic
5
24
%13932a501
0’ ’’I III III1020304050
60 70
8082
FullyThrottle openingFUIIYclose
d
(degrees)open
7FUO75
ECM
A-54
(1989 models)
Throttle-position
sensor
NOTE* mark is applicable for 1990, 1991, 1992, 1993 models. 12A0432
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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-29
Operation
The throttle-position sensor is the same for the ECM of engine and transaxle. The ECM estimates
the acceleration status of the vehicle according to
the sensor output.
Service data indication
) Code No 1 lndrcatron
Display
I
l4 1
The output voltage of the throttle 14: TPS 549mV-postron sensor IS indicated.I
ECU terminal voltages (when connector is connected)
Terminal
No.Condition Terminal
voltage
51
1 !
Throttle-posrtlon sensor signal During idleo-1v
When fully open5v
/ When there is damaged or disconnected wiringIov I
Checking the throttle-position sensor circuit (with the connector disco\
nnected) Terminal Connection
destrnation or MeasurementNo measured part Tester connection
Check condition
Standard
51Throttle-positron
sensor Resistance
51 -ground Change according to the throttle0.5-5 k0opening should be smooth and
within the standard value range shown at the right.
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33B-30 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[51 HIGH-PRESSURE SWITCH CIRCUITShield plate
/v (right)
/Lo&pressure switch
High-pressure
switch
High-pressure
switch
o~~---~---~~-~l
760 (108)950 (135)
Pressure kPa (psi)
72AO172
FCI I
I-Detection ofhigh-pressuretank pressure
1
/\
0m
A-ln
6 A-38
High-pressure
switch12 A0493
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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-31
Operation
The high-pressure switch is switched ON and OFF by the pressure in the high-pressure tank, and as a
result the ECU functions to control the activation
and stop of the compressor.
When the pressure in the high-pressure tank be-
comes 760
kPa (108 psi) or lower, the high-pressure
switch is switched ON, and as a result the ECU
sends the drive signal to the compressor. Conversely, when the pressure of the high-pressure
tank becomes 950
kPa (135 psi) or higher, the
high-pressure switch is switched OFF, and the
compressor is stopped two seconds thereafter.
Note, however, that the compressor is not ac-
tivated, even if the high-pressure switch is switched ON, if the return pump is in operation. Note also
that there is no diagnostic function for the
high-pressure switch.
Service data indication Code No
lndlcationDisDlav
15Indicates the ON/OFF status of the
high-pressure switch. 15: HIGH PRESS. SW. ON/OFF
I
ECU terminal voltages (with connector connected)
Terminal
No.Signal ConditionTermina
l
voltaaeI
59
High-pressure tank pressure signal
When high-pressure switch is ON (low pressure)
o
v
When high-pressure switch is OFF (high pressure)
5v
Checking the high-pressure switch circuit (with the connector disconnec\
ted)
Terminal Connection destination or
M
easurement
Nomeasured part Tester connection ,
Check conditionStandard
59High-pressure
switch Reststance
59-36
High-pressure tank internal
pressure 760 kPa (108 psi) orlower Continuity
High-pressure tank internalpressure 950 kPa (135 psi) orhigher
Nocontinurty
Troubleshooting hints
Malfunctlonmode
Malfunction probable cause
MalfunctionNote
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Harness
wlrlngdamage ordlsconnectlon
Harness wiring damage or disconnection, or
Improper switch contact Compressor doesn’t operate.-
Harnessshort-crrcuit
Air leakage. Harness short-circuit, or switch short-circuit, O-ring
worn or damaged. Compressor operates without stopplng.DiagnosticNo.55output.
Rolling control feehng
of Incompatibility. very-freauent oaeration of compressor.