display MITSUBISHI GALANT 1989 Service Workshop Manual

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.

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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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-33
Operation
When the ignition is switched ON, the ECS power relay is also switched ON, and power is supplied to
the system. At the same time, the ECU switches
ON the solenoid
valve power relay, and power is
supplied to the solenoid valve activation circuit. As a
result, system operation is possible.
Diagnostic
When problems such as damage or disconnection of the heavy-line circuit, or fusing of the contacts of
the solenoid valve power relay, etc. occur, the alarm When the ignition switch is switched OFF after driv-
ing, the three-minute OFF delay timer makes
vehicle-height adjustment (down only) possible for a period of three minutes, thus preventing the vehicle
height from increasing while passengers get out of
the vehicle, etc.
light illuminates, and control is as described in the
table below.
Diagnostic No. 42 Attitude control
Rolling control
onlv stoos.
Damping force
Vehicle-height Switch acceptance
control control
/ HIGHSPORTAUTOSOFT
Held at MEDIUM
Rolling control
Not acceptonlv stoos
Service data indication
CodeNo /Indication Display
16Indicates ON/OFF status of the
iqnition switch. 16: IGNITION SW. ON/OFF
ECU terminal voltage (when connector is connected)
valve power relay output
26
Solenoid valve power relay drivesignalWhen solenoid valve power relay is ON
When solenoid valve power relay is OFFB+
B+: Battery positive voltage
Checking the ACTIVE-ECS power source circuit (with the connector discon\
nected)
Terminal Connection destination or Measurement ’No.measured part Tester connection
Check condition
5Ignition switchi Voltage5-groundIgnition switch OFF
Ignition switch
OFF-O
N
8Solenoid valve power
Voltage8-groundTerminal 26 open.
relay
Terminal 26 groundedStandard
o
v
O+B+
ov
O-B+
10ECU back-up power
sourcei Voltage1 O-ground
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B+: Batten/ positive voltage

ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-39
Operation
The ACTIVE-ECS system functions, in order to improve the “air drag” characteristic, to adjust the During the nighttime, however, in order to prevent
vehicle height to the LOW setting at the front end deviation of the headlight beams from the required
only during the daytime when the vehicle speed directional path, the vehicle height is adjusted to the
reaches 90 km/h
(56 mph) or higher and continues LOW setting for both the front end and the rear end
at that speed for a period of ten seconds or longer. when signals from the headlight relay are input.
Service data indication
Code No.lndlcation
Display
18Indicates the ON or OFF status of
18: HEADLAMP SW. ON/OFF
the headlight switch.
ECU terminal voltages (when connector is connected)
/
TerminalNo. Slgnal
ConditionTerminal
voltage
89 Headlight switch
signal When headlight
switch is ON
When headlight switch is OFFB+
o
v
When there is damaged or disconnected wiring
5vJ
B+: Battery positive voltage
Headlight switch circuit (with the connector disconnected)
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TeKJna’
89
Connection destination Measurement Tester connectionCheck conditionStandard
or measured Dart
Headlight relayVoltage 89-groundph&the headlight switchov
rt$z; the headlight switchB+
~.A.-II___B+: Battery posrrrve voltage

ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-41
Operation
The slitted disc installed to the steering shaft
inter-
rupts, or allows light to pass with the result that
electric signals corresponding to the
angular-veloci-
Diagnostic
If there is damage or disconnection of the heavy-line
circuit, the alarm light illuminates and control is as ty of the steering wheel movement are detected
and passed to the ECU.
described in the table below.
Diagnostic No. Attitude control Damping force
control Vehicle-height
control
HIGH
Switch acceptance
SPORT AUTO
SOFT
I
21Control stop Held at MEDIUM
Held at NORM
I
Not accept
vehicle height.
I
Service data indication
Code No. Indication
Display
21Indicates the ON or OFF status21: STEER. SNSR. ST1 ON/OFF ST2 ON/OFF
individually for STR 1 and STR. 2.
ECU terminal voltages (when connector is connected)
TerminalNo.Signal Condition Termrnal
voltage
25 Power source for sensor
When the ECU is activated
5v
53Steering angular-velocity sensor (1)When the photo-interruptor is ON
o
v
60
’Steering angular-velocrty
sensor (2)When the photo-interruptor is OFF3.5y
When there is damaoe or disconnection of the harness5v
-“.
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36Sensor circuit
ground Constantly ov
Checking the steering angular-velocity sensor circuit (with the connect\
or disconnected)
Terminal Connection destination or MeasurementNo.measured partTester connection
Check condition
Standard
Steering angular-velocity Resistance
sensor power-supply
circut
25-36 Connect the tester’s t-i probe to
Continuity
terminal 25, and the (+ ) probe exists. (Theto terminal 36. indicator
Note: fluctuates
Even
If the result is good, the
sensor must not be judged to be
working.
Steering angular-velocity Resistance
sensor 53-36
Turn the steering wheel slowly.
NocontinuityIContinuity

ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-47
Operation
The vehicle-speed sensor is a reed switch type with pulse signals being \
sent four times for each rotation of
the transaxle output gear.
Diagnostic
If there is damage or disconnection of the heavy-line
the alarm light illuminates and control is as
de-
circuit, or a malfunction of the vehicle-speed sensor, scribed in the table below.
Diagnostic No. 24
Attitude control Damping force
Vehicle-height Switch acceptance
control controlHIGHSPORTAUTO SOFT
Control stop
Held at MEDIUMHeld at NORMAL
Not accept
Service data indication Code No lndrcation
Display
24 Indicates the vehicle speed Input
to
24: SPEED SNSR. 0 km/h
the ECU (including the simulated
vehicle speed)
ECU terminal voltages (when connector is connected)
ITerNmo_na’ConditionTerminal
voltage
I I
58 /
I
Vehicle-speed signal1 When the vehicle-speed sensor reed switch is ONo
v
IIII
*When the vehicle-speed sensor reed switch is OFF8V
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*In order to supply the EPS pull-up power
(8V)
Checking the vehicle-speed sensor circuit (with the connector disconnec\
ted)
Termrnal
Connectron
destination or M
easurement
No measured part
Tester connection
Check conditionStandard
58 Vehrcle-speed
sensor
Resistance
58-groundWith the battery’s (-1 termrnal
Continuity
disconnected, move the vehicleIback and forth.Nocontinuity
Troubleshooting hints In actual urban driving, it is not so likely that the
sensor fails.., ^_^.tnrottle IS kept 3U% or more open for more than 30
seconds. Therefore, the conditions have been This takes into account that the vehicle speed sen-
somewhat stricter to prevent unnecessary applica-
sor is shared by many systems such as EPS,
Auto-
tion of the fall safe function due to the racing of the cruise control, etc. and that the failure of the sensor
engine when stopped. However, the vehicle may can also be detected from the state of these sys-
terns.run uncontrolled for some distance when the speed

ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-49
Diagnostic
If, because of damage or disconnection of the heavy-line below. Note, however, this diagnostic signal is given if
circuit, or a malfunction of the rear-pressure sensor, etc., there is an overload.
a htgher than normal value of the internal pressure of the
l :1989 models
air springs is indicated continuously, the alarm light The alarm light does not illuminate for 1990, 1991,
illuminates*, and control is as described in the table 1992, 1993 models.
I1
Damping forceVehicle-heightSwitch acceptanceDiagnostic No.Attitude controlcontrol
control
HIGH 1 SPORT 1 AUTO 1 SOFT
25Control stopNormal
Only the vehicle-height
increase Not Accept
operation control function stops. accept
I
1990, 1991, 1992, HIGH-AUTO change possible. If the above diagnostic num\
ber is detected, the damping force that is
1993 models:the base of the SOFT mode and AUTO mode changes to the MEDIUM damping fo\
rce.
Service data indication
1 Code No. 1Indication
Standard valueDisplay
25Rear-pressure sensor output Fluctuates within a range of 0.5V
to 4.5V
25; RR. PRESS. SNSR. 2.45V
voltage when the body is shaken from side to side.
Condition
Reference value
Front seats: 2 persons When HIGH vehicle height
When NORMAL vehicle height
When LOW vehicle
height
1.6OV
0.9ov 0.86V
ECU terminal voltages (when connector is connected) ConditionTerminal
voltage
25Power supply for sensor
37Rear air spring pressure signal When the ECU is activated
Low rear air spring pressure
High rear air spring pressure
5v
0.5vI
4.5v
When wiring IS damaged or disconnected5v
35 Sensor circuit ground
Constantly o
v
Checking the rear-pressure sensor (with the connector disconnected)
Terminal Connection destination or MeasurementNomeasured part
Tester connection
Check condition
Standard
ERear-pressure sensorResistance
25-35 Constantly Approx.
All resistances 5 kll
37Rear-pressure sensor
Resistance
37-35 Change should be smooth (accordingO-5 klloutput to the air pressure applied to the rear
-pressure sensor) within the standard
value range shown at the right
Troubleshooting hints (mechanical malfunctions) Malfunctionmode Malfunction probable cause
Malfunction
Note
Harness
short-circuit Because of a short-circurt
of the harness, etc , Insufficient control of the attitude, resulting in a
-no correction of the air-supply and exhaust time feeling of incompatibility
can be made to compensate for a loaded
condition of the vehicle. Air leakage
Wear, damage, etc. of the O-ring
Vehicle height decreases if not corrected-
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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-51
Operation
When the brake pedal is depressed, the stop light
switch is switched ON and
1% is sent to the ECU,
thus resulting in the detection that braking is in progress.
Service data indication
Code No. Indication
Display
I 26 I
Indicates the ON or OFF status of26; STOP LAMP SW.
the stop light switch.ON/OFFI
ECU terminal voltages (when connector is connected)
Terminal Signal ConditionTerminal
No voltage
83 Stop light switch signal
When the stop light switch is ON o
v
When the stop light switch is OFF
B+
B+: Battery positive voltage
Checking the stop light switch circuit (with the connector disconnected\
) Terminal Connection destination or
MeasurementNo measured part Tester connection
Check condition
Standard
83 Stop light switch Voltage
83-groundIgnitionDepress the brake
switch ON pedal.B+
Do not depress the
o
v
brake pedal.
B+: Battery positive voltage
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-,

33B-52
ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[15] BACK-UP LIGHT SWITCH CIRCUIT Ignition switch (IG,)
c-43

-T----
From 1990 models 1989
models
C-23
-1
From 1990 models Junction
block
B-21
C-23 A
fiYl%mq
1989 models
F-lfi
& 12 *
c
2 12,16
ifi
Back-up
light switch
+ From 1990
models
*
To back-up
light
ECU12AO400
Checking the back-up light switch circuit (with the connector disconnec\
ted)
Terminal Connection destination or
,v,easurement TesterNo.measured Dartconnection Check condition
Standard
72Back-up light
Voltage72-groundWith the shift leverIgnition switch OFFo
v
shifted to the REVERSE position Ignition switch ON
B+
Service data indicationB+: Battery positive voltage
Code No. Indication Display
32Indicates the ON or OFF status of
32; M/T
BACK LAMP ON/OFF
the back-up light switch.
ECU terminal voltages (when connector is connected)
TerminalNoCondition Terminal
voltage
72Manual transaxle back-up signal
I
When the back-up light switch is ON
When the back-up light switch is OFF
1
1 TSB Revision
B+
o
v
I1B+: Battery positive voltage

ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-53
1161 DOOR SWITCH CIRCUIT
L
ECU
Batten/
Dome light
ETACSunit
b +G Door light2 Door light
6? Door light
El---- g-l---
sl--
z Door light
I
Front door swatchRear door switch
Service data indication
Code NoIndication
Display
33Indicates the ON or OFF status of33: DOOR SW. ON/OFF
the door switch (Indicates ON if at least one door is opened.)
ECU terminal voltages (when connector is connected)
Condition Termrnal
voltageI
Door switch signal When a door (at least one) is opened
When the door is closed o
v
B+
Checking the door switch circuit (with the connector disconnected)B+: Battery positive voltage
ITerminal Connection destination or MeasurementNo.measured part
Tester connection
Check conditionStandardI
74Door switch
Resistance74-groundDisconnect the battery’s negative (-)
terminal and close all doors.
Disconnect the battery’s negative (-)
terminal and open the doors
one by one.Nocontinuity
Continuity
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