1989 MITSUBISHI GALANT Service Repair Manual

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.
TSB Revision

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)
TSB Revision
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
TSB Revision

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
-“.
TSB Revision
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

33B-42
ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
IO] FRONT-HEIGHT SENSOR CIRCUIT
.ever
Seysor
,..e
Relationship between N (normal vehicle height) and othervehicle-height levels
High 1
Normal 50
(1.97)
40(1.57)
30(1.18)
201.791
10C.39)
0
tEH (highest)._--
HH (higher than HIGH)
H (HIGH vehicle height)
NH (higher
than NORM)
N (NORMAL vehicle height)
EL (lowest) A-27
[Unit: mm
(in.11
Front-helghf
sensor
Operation
The front-height sensor detects (by detecting the
sistors, and the slits in the disc thus interrupt, or let
relative position of the body and the front axle) the
action movements (bouncing, nose diving, etc.), pass, the light beams between the light-emitting
diodes and the photo-transistors. By employing the data gathered in this way, the
sen-
sor can detect the vehicle height as any one of the
nine level classifications.
and the vehicle height, of the front of the vehicle,
The rotating disc plate rotates in the area between
four pairs of light-emitting diodes and photo-tran-
TSB Revision

ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting 33B-43
Diagnostic
When a signal (error code) indicating an abnormal
condition (resulting from damage or disconnection
of the heavy-line circuit, or a malfunction of a photo-transistor, etc.) is input, the alarm light
illu-
minates and control is as described in the table
below.
Diagnostic No. Attitude control Damping force
Vehicle-height
~Switch acceptance
control control
HIGHSPORT 1AUTOSOFT
22
Control stopj Held at MEDIUM Control stop Not accept
Service data indication
Code No lndrcation
Indication example
22Current vehicle-height level (ERRORWhen 22:N1111when there is a malfunction)
normallndrcates
the ON or OFF status of lndtcates
the vehicle-height-Status of each photo-interruptor
level. 1: ON,O: OFF
each
photointerruptor.If mal-22; ERRORfunction
0010
Indicates that an error code isL Status of each photo-interruptor
beina output.l:ON.O:OFF
ECU terminal voltages (when connector is connected) Termrnal
NoCondition
Terminalvoltaae
25
54,5556.57Power source for sensor
Front vehicle-herght signal
When the ECU is activated
5V
When the photo-rnterruptors are ON
o
v
When the photo-interruptors are OFF
5V
1 36/ Sensor circuit ground I ConstantlvIo
v
I
Checking the front-height sensor circuit (with the connector disconnect\
ed)
Terminal
Connectron
destination cNomeasured part
:zFront-height sensor
power-supply crrcuit
22
56
57
Front-height sensor
Resistance
brMeasurement
Resistance 25-36Tester connection
54-36
55-36
56-36
57-36
t
Troubleshooting hints (mechanical malfunctions) Check condition
Standard
Contact the tester’s
(-1 probe to Contrnuity
terminal 25, and the ( + ) probe to(Theterminal 36.
rndrcator
Note fluctuates)
Even if the result is good here,
the sensor must not be judged
tcbe certainly good.
Contact the tester’s
(-1 probe to
terminal 25, and the (+ 1 probe to
terminal 36, and check to be sure
that there is continuity, leave the
connections as they are.
Connect the tester’s
(-1 probe to
each terminal of the wiring
harness connector, and the
(+ Jprobe to terminal 36
Separate the lever (of the height
sensor) from the rod, and slowly
nave the lever up and down.
No Continurty
IContinuity
Malfunction mode Malfunction probable cause
Malfunction
Note
Improper Because of the improper adjustment of the
-adjustment of the
front-height sensorfront-height sensor rod, a signal not
l When the engine is stopped and left as it is,
corresponding to the actual vehicle height is the height of onlythe front end decreases to
rodbeing sent to the ECU lower than the NORMAL vehicle height
l With the engrne running, the height of the front
end IS lower than the NORMAL vehicle
height
l With the engine running (AUTO mode and NORMALvehicle

hetght). the height of the front
end becomes higher than the NORMAL helght)
1 TSB RevisionI

33B-44 ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
[ll] REAR-HEIGHT SENSOR CIRCUIT
1989 models
F-18
-1
F-l 9
pjimlq
piTgs%q
c-07
D-27
G-05
High
I
Normal50 (1.97)
4..:::.:.:_~-.^::::::::“.“::i
+E
jr;::::::::::_:
40 (1.57)
30 (1.18)
LowI[Unit: mm (in.11
ECU
1 Rear vehicle-height/fisjnmy3tp I (I
Rear-height sensor12AQ414
-LL (lower than LOW) HH (higher than HIGH)
H (HIGH vehicle height)
NH (higher than NORM)
N (NORMAL vehicle height)
NL (lower than NORM)
L (LOW vehicle height)
12AO182
Operation
The rear-height sensor detects (by detecting the relative position of the body and the rear axle) the
action movements (bouncing, pitching, etc.), and
the vehicle height, of the rear of the vehicle. The
rotating disc plate rotates in the area between three
pairs of light-emitting diodes and photo-transistors, and the slits in the disc thus interrupt, or let pass.
the light beams between the light-emitting diodes
and the photo-transistors. By employing the datagathered in this way, the sensor can detect the vehi-
cle height as any one of the seven level
classifica-
tions.
TSB Revision

ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshootina 33B-45
Diagnostic
When a signal (error code) indicating an abnormal condition (resulting from damage or disconnection
of the heavy-line circuit, or a malfunction of a photo-transistor, etc.) is input, the alarm light
illu-
minates and control is as described in the table
below.
Diagnostic No. Attitude control
23Control stop
Service data indication Damping force
control
Held at MEDIUM Vehicle-heigh
t
Switch acceptance
control
HIGH SPORT AUTOSOFT
Control stop
Not accept
Code No Indication
Indication example
23 Current vehicle-height level (ERROR When 23;N
1111when there is a malfunction)
normal
Indicates the ON or OFF status of Indicates the vehicle-height
levelL Status of each photo-interruptor
each photo-interruptor. 1: ON, 0. OFF
If mal-23; ERROR0010
function Indicates that an error code IS
being output.L Status of each photointerruptor1: ON, 0. OFF
ECU terminal voltages (when connector is connected) Terminal
No.Signal Condition
25 Power source for sensor
When the ECU is activated
61.62
63,64Front vehicle-height sIgnalWhen the photo-mterruptors are ON
When the photo-interruptors are OFF
36 Sensor circuit ground
Constantly Terminal
voltage
5v
o
v
5V
o

v
Checking the rear-height sensor circuit (with the connector disconnecte\
d)
rTerminal Connection destination or

M
easurement
No measured part Tester connection
Check conditionStandardRear-herght
sensor
power-supply circuit Resistance
25-36 Contact the tester’s (-) probe to
Continuity
terminal 25. and the
(+) probe to(Theterminal 36 indrcator
Note fluctuates)
Even if the result is good here,
the sensor must not be judged to be certainly good.
61
Es
Rear-height sensor A Resrstance
61-36No
F
Contact the tester’s (-)
probe to
62-36 terminal 25, and the ( +) probe toContinuity
63-36 terminal 36, and check to be sureIthat there is continuity; leave the Continuity
connections as they are.
Connect the tester’s
(-1 probe to
each termrnal
of the wiring
harness connector, and the
( +)probe to terminal 36. Separate the lever (of the height
sensor) from the rod, and slowly
move the lever up and down
64
- _. .
DResistance64-groundConstantly Continuity
1 roubleshooting hints (mechanical malfunctions)
Malfunctionmode Malfunction probable cause
MalfunctionNote
Improper Because of the improper adjustment of the l When the engine is stopped and left as it IS,
-adjustment of the
rear-height sensorrear-height sensor rod, a signal not
the height of only the rear end decreases to
rod correspondrng
to the actual vehicle height IS berng
sent to the ECU lower than the NORMAL vehicle height.lWith the engrne running, the height of the rear
end is lower than the NORMAL vehicle height
lWith the engine
running (AUTO mode and
NORMAL vehicle herght). the height of the rear
end becomes higher than the NORMAL height).
TSB Revision