MITSUBISHI GALANT 1989 Service Repair Manual

33B-32 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[6] ACTIVE-ECS POWER SOURCE CIRCUIT
Relay box
‘
Solenoid :valve .
A-06X
*‘:
b OFF
J Iv! 1
EyllAy 1 Junction block
4‘B
IF-17
j$----hJ _____ 15---~4&L---v----.6
iI
1234
5
m67891F-18
b
;
/ b i-i
Valve actwation3m,nute* OFFcontrol circuitA^,^., .i”..%*
ECU
Sfabdization WwWL guse circuit---------JI
L---
T
122042lSolenoid valve power source
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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

33B-34 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[7] ACTIVE-ECS indicators circuit
Battery
Column switch
-------
c n-21
f
ACTIVE-ECS 1indicator
I
(From 1990 models)
ECUII
F-17
Power source,circuif
/
EEzQ15~JgJ 1 ,2-LR
i181lllumlnatlon lightSPOK
1 1c
1’
I’
II
I 1
II
I IiI’
I I
/I
I’I 1
NOTEI-
* mark is applicable for 1991, 1992, 1993 models.ECUI TSB Revision

ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-35
Service data indication
Code No Indication
Standard value
17ECU input voltage indications when When switches are openSPORT, AUTO, SOFT, HIGH5V
switches are pressed.When SPORT switch
is ONOV
When AUTO switch is ON1.53v
When SOFT switch is ON 2.71V
When HIGH swrtch
is ON 4.02V
ACTIVE-ECS indicators check chart
1.Checking the power source circuit
Disconnect the battery terminals, and, after erasure of the
ECU mode memory, turn the ignition key to the ON position.
1
Indication example
17: MANUAL CNG. SW
4.03v
The sound of the damplng force switching actuators (steplNoThe ACTIVE-ECS power relay doesn’t function
motors), installed at the front struts and at the rear shock
--+l Disconnected or damaged wiring of the fusible link, the
absorbers, will be heard. fuse and/or the harness between the battery and the AC-TIVE-ECS power relay contacts
Yes
When terminal 15 of the ACTIVE-ECS indicator is grounded,yes
the “SOFT” damping force characteristic indicator and the -lDisconnected or damaged wiring of the ground line 15 of
“NORM” vehicle-height indicator will
illuminate.the ACTIVE-ECS indicator.
No
Approximately
12V is measured when the voltage betweenNo
ground and terminal 20 of the indicator and the ACTIVE-ECS --+l Disconnected or damaged wiring between the AC-
is measured. TIVE-ECS power relay and ECS Indicator
terminal 20.
I Yes
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-. ACTIVE-ECS Indicator power source circuit OK Proceed to
checking of the individual ACTIVE-ECS
lndlcators

33B-36 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
2.Checking the individual ACTIVE-ECS indicators
After disconnecting the control unit’s connector, turn the nition kev to ON
1
All items shown in the tables on the next page are satisfied~~ 8 Poor or improper contact of the ACTIVE-ECS indicator
when each terminal of the ACTIVE-ECS indicator’s connector Fand the connector terminal.is grounded and the resistance is then measured. l ACTIVE-ECS malfunction
Yes
All items shown in the tables on the next page are satisfied
when each
terminal of the wiring harness connector discon-
No
l Damaged or disconnected wiring or large contactnetted from the control unit is grounded and the resistance__*resistance, between the ACTIVE-ECS indicator and the
is then measured. connector of the control unit.
Yes
I
lPoor or improper contact of the control unit and the con-
c nectar terminal
.
0 Control unit malfunction.
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ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-37
r
ACTIVE-ECS indicator
Control unit wiring
connector terminal No harness connector
Normal
terminal No
All termrnals
are not
I
-The’SOFT” damprng
force characteristic indicator and the “NORM”
earthed vehicle-height indicator illuminate.
I
1-1 The illumination light illuminates when battery voltage is applied to t\
erminali 19.
276In addition to the “SOFT” and “NORM” indicators, the “MED\
IUM” dampingi force characteristic Indicator also illuminates.
I3/88
In addition to the “SOFT” and “NORM” indicators, the “SOF\
T”*’ switch
indicator also illuminates.
I
Ll90Connect a circuit tester and
measure the resistance when
the control mode and
vehicle-height select switches
are pressed
1 b;h is pressed.1 E;i;yi;;a 1
SOFT1 Approx. 890 fZ 1
/ HIGH1 Approx. 3090 121
577In addition to the “SOFT” and “NORM”
Indicators.
the “HIGH” switch
indicator also illuminates 6*2
-In addition to the “SOFT” and “NORM” Indicators, the alarm light
illuminates.
787In addition to the “SOFT” and “NORM” indicators, the “SOF\
T” swatch indrcator
also illuminates.
975The “NORM” vehicle-height rndicator
illumination stops, and the “HIGH”
vehicle-height indicator illuminates; the “SOFT” damping force cha\
racteristic
indicator remains illuminated.
1085The “NORM” vehicle-height Indicator illumination stops, and the “\
LOW”
vehicle-height indicator illuminates; the “SOFT” damping force cha\
racteristic indicator remains illuminated.
1178In addition to the “SOFT” and “NORM” indicators, the “AUT\
O” switchindicator also illuminates.
1380In addition to the “SOFT” and “NORM” indicators, the alarm l\
ight
illuminates.
1486 In addrtion
to the “SOFT” and “NORM” indicators, the “MEDIUM” and\
“HARD” damping force characteristic indicators also illuminate
15-The “SOFT” damping force characterrstic
indicator and the vehicle-herghtindicator illuminate.
17
1971
-
The buzzer sounds.
The “SOFT” and “NORM” indicators become slightly
dimmer when terminal
20 is connected to terminal 19
NOTE*l:1989 models
“SPORT” modeisapplicable for1990, 1991,1992,1993models
l *: Applicable to 1989 models only.
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33B-38 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[8] HEADLIGHT SWITCH CIRCUIT
Battery1I
4Ignition
Tswitch (ACC)
c-43 l-
(From 1991 models)
(From 1990 models) A-01X
Head-
light
ECU
-L
II;
50 >
c
;-ii -I
Kin.>r(
3
OA
/\7'6
1
I
To column switch TL
‘89F-l 6
IITo meter (upper beamindicator light)
8A
headlight
pjjimmj
C-23 (From 1990 models)
12*0642
NOTE* mark and chain line indicate 1991, 1992, 1993 models.
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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

33B-40 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[9] STEERING ANGULAR-VELOCITY SENSOR CIRCUIT
\ k=3 -2
Steering angular-veloclty sensor- m0439
Photo-Interruptor B/12A0208
F-19ECU
heel
anoular- 1
F-06
pT$q
pFlz$EJ c-07
A
d2 7
I!
t
ii --
ii -I
7 aC-68
12 3
P4r _ v n
w jTT~jR-$+j 1
Steering angular-velocity sensor
-1
12AO411
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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