check engine MITSUBISHI GALANT 1989 Service Repair Manual

ACTIVE-ELECTRONIC CONTROL SUSPENSION - ;;:i~%:?~~“~
33B-95
Adaptor E (MB991227)
Shut-off valve 12A.0350
iigh-pressure
witch
Air-pressure gauge (MB991075)
Adaptor C
(MB991 075.q
,daptor E (MB991226) /P-
3intH &‘xb
2.
3.
4.
5.
Connect the gauge side air tubes of the special tool (air-
pressure gauge) to the disconnected air tube and joint,
connecting them via the special tube (adaptor E).
NOTE
The shut-off valve of the air-pressure gauge should be closed.
Start the engine and activate the compressor.
NOTE
If the system is in normal condition, the compressor will
be activated after the engine is started, because the
pressure within the high-pressure tank has decreased.
After activation of the compressor, the pressure within the high-pressure tank will increase; check whether or not the
pressure is the standard value when the compressor is
stopped.
Standard value: 900
kPa (128 psi) or higher
Gradually open the shut-off valve of the air-pressure gauge
while watching the indicator of the air-pressure gauge; check whether or not the pressure that actuates the
compressor’s operation (when the pressure within the
high-pressure tank has dropped) is within the standard
value range.
Standard value:
710-810 kPa (101-115 psi)
NOTE
The ON/OFF status of the high-pressure switch at this time can be checked by the special tool MB991269
(1989
models), MB991341 (1990, 1991, 1992 models).
(Refer to
P.33B-18.)
6.If the pressure within the high-pressure tank is not within
the standard value range when the compressor is stopped
(high-pressure switch OFF) or the compressor is activated
(high-pressure switch ON), remove the reserve tank
assembly and replace the high-pressure switch.
LOW-PRESSURE SWITCH (LOW-PRESSURE TANK
SIDE) ACTUATION PRESSURE CHECK
1. Remove joint
H of the blue-marked air tube (for the left
front valve) of the front solenoid valve assembly.
2.Connect the special tool (air-pressure gauge) between the
disconnected air tube and the front solenoid valve assem-
bly by using the special tools (adaptors
E and C).
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338-96
ACTIVE-ELECTRONIC CONTROL SUSPENSION - ;;~:;u~:iusment
Low-pressure
switch
PressurekPa (psi)
I
OFF
t
140 (20)
70 (10)
ON
12AO226
12A04P
3.Connect the scan tool, start the engine, and wait until the
compressor stops (the high-pressure switch is OFF).
4. Input simulated vehicle-speed signals
[3 km/h (2 mph) or
higher].
5. With the simulated vehicle-speed signals still being input. conduct actuator test No. 09 (left turn) or No.
IO (right
turn) so as to increase the pressure within the
low-
pressure tank chamber.
6. During the actuator test, monitor the pressure gauge indication and check whether or not the pressure when
the return pump activation starts (i.e., the maximum gauge reading) and the pressure when the return pump
stops are both within the standard value.
Standard value: Return pump actuation pressure
loo-180 kPa (14-26 psi)
Return pump cut-off pressure 50
kPa (7 psi) or lower
7. If the internal pressure of the low-pressure tank is not within the standard values when the return pump opera-
tion is actuated (i.e., the low-pressure switch is OFF) or
when the operation of the return pump is stopped
(low-
pressure switch ON), remove the reserve tank assembly
and replace the low-pressure switch.
G-SENSOR OUTPUT VOLTAGE CHECK 1. Unload the vehicle and move it to a horizontal surface.
2.Connect the special tool (scan tool) and start the engine.
3. Check whether the G-sensor output voltage is within the standard value range when the vehicle-height is theNORMAL vehicle-height.
Standard value:
2.520.16V
4. If the G-sensor output voltage is not within the standard value range, check the installation condition of the
G
sensor; if there is bolt loose, deformation of the body,
etc., repair it. If the problem is not repairable, replace the
G sensor.
NOTE
If the G-sensor installation surface is at an angle (tilted)
due to body deformation or some other cause, a washer(s)
or shim(s) may be used to make an adjustment so that the
output voltage is within the standard value range.
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SERVICE BRAKES - Anti-lock Braking System Troubleshooting35-15
ANTI-LOCK BRAKING SYSTEM
TROUBLESHOOTINGM35EElAE
PARTICULAR CHARACTERISTICS OF
THE ANTI-LOCK BRAKING SYSTEM
Models equipped with the anti-lock braking system
(A.B.S.) may exhibit one or more of the following
characteristics from time to time, but none of these
is abnormal.
(1)
(2)
A pulsing feeling in the brake pedal, or vibration
of the body or the steering wheel, when the
anti-lock braking system is activated by sudden
braking or by braking on a slippery road surface.
Actually, this phenomenon is an indication that
the anti-lock braking system is functioning nor-
mally.
When the vehicle speed reaches approximately
6 km/h (4 mph) after the engine is started and
the vehicle starts off (for the first time), awhining motor noise may be heard from the
engine compartment if the vehicle is traveling in
a quiet place. This noise is simply the result of a
self-check being made of the anti-lock braking
system operation.
TROUBLESHOOTING METHODS
Problems related to the anti-lock braking system
(A.B.S.) can be classified into two general categor-
ies: problems in the electrical system and those in
the hydraulic system. For problems in the electrical system, the on-board
diagnostic is built into the electronic control unit
(E.C.U.) causing the A.B.S. warning light to illuminate
as a warning to the driver. In this instance, checks
can be made by using the scan tool and oscillo-
scope.
Problems in the hydraulic system (poor braking,
etc.) can be located in the same way as for ordinary
brakes. There is, however, the necessity to check to
determine whether the problem is related to ordi-
nary brake components or to the components re-
lated to the A.B.S. To make this check, use the scan
tool.
HOW TO USE THE TROUBLESHOOTING
FLOW CHART
(1) Using the flow chart, check the ABS warning
light light-up sequence. Read the diagnostic
trouble codes and check the condition of bra-
king operation.
(2) Following the check chart listed in the remedy
column, perform the checks. There are [Expla- nation] and [Hint] in each check chart. Refer to
them when troubleshooting.
NOTE
ECU: Electronic control unit
HU:Hydraulic unit
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35-16SERVICE BRAKES - Anti-lock Braking System Troubleshooting
TROUBLESHOOTING (ABS-FWD)
Confirm condition in the following way and diagnose accordingly.
Ioes the ABS warning light illuminate as describedpower to the ABS ECU is interrupted and the
lelow up to the time the engine starts?ABS warning light remains lit because the valve
1) When the ignition key is turned to the “ON” relay is OFF.
position, the ABS warning light blinks twice for (3) When the ignition key is turned from the “START’
approximately 1 second due to the ABS ECU (as position to the “ON” position, the ABS warning
a self check of the valve relays is performed), light blinks twice for approximately 1 second
and goes out and stays out. (during this time a recheck of the valve relays is
2) With the ignition key in the “START” position, performed), and then goes out and stays out.
ABS warning
,,lseq (se+
lightII
OFF -I
Ignitionkey
ABS warnmg/;,ght68A009314A0589
YAS rICONTINUE TO NEXT PAGENo
No.
Trouble condition
ABS warning light does not light up at all.
ABSwarnina
ON
OFF
1light -
lgnltionkey
I14 A0590
When the ignition key is turned to the l Fail safe is functioning due to ECU on-
“ON” position, it remains lighted. board diagnostic
ABSwarning
2lightOZ7
l Short in ECU warning light drive circuit
l Malfunction of ECU
lgnitlonkev
ACC. LOi+14A0591
Does not illuminate when ignition key is
in “START” position.
ABSwarning
3light
Ignition
key ACC. LO:+14AO592
Major causes
l ABS warning light bulb is burnt out.
l Open in ABS warning light electrical circuit (check for blown fuse)
l Malfunction of valve relay
l Break in harness between ABS warn- ing light and HU
l Break in harness between HU and body ground Remedy
Check, using flow
chart A (Refer to
P.35-21.)
Check, using flowchart B (Refer toP.35-24.)
Check, using flow:hart C (Refer to ‘.35-26.)
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35-22SERVICE BRAKES- Anti-lock Braking System Troubleshooting
- N

o
With the ignition key in the “ON” posi-
Check fuse No. 9. If it is
tion. do other warning lights illuminate?
* blown, correct the cause of
the blown fuse and thenreplace the fuse.
I
Yes
Turn the ignition switch OFF and check.
4II., III,
Is the ABS warning light normal? (CheckNo cABS warning light bulb Replace ABS warning
for burned bulb.)burned.* light bulb.
I
Yes
NoThe harness between the
combination meter from
* fuse No. 9 is broken.
1
Repair harness.I
Circuit in combination metercRepair or replace com-
is broken. bination meter.
Yes
Is there continuity between terminals No.NoMalfunction of combination Repair or replace combi-
;,d”,l” No. 17 on the combination meter -meter
nation meter
Yes
Are instrument panel wiring harness, _
Noc Connect connectors firmly.
engine compartment wiring harness,
body wiring harness and ABS wiring
harness connectors connected properly? (Check for pins pulled out or
bent, repair as needed.)
Yes
Broken wire in ECU, valve relay or both
drive circuits. Check and repair both
circuits.
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35-24
SERVICE BRAKES - Anti-lock Braking System Troubleshooting
B ABS warning light illuminated after the engine is started and remains o\
n.
[Explanation]
This is the symptom when the ABS ECU does not
power up due to broken ECU power circuit, etc.,
when the fail safe function operates and isolates the
system or when the warning light drive circuit is
short circuited.
[Hint]
Check the on-board diagnostic output and if there is
no output voltage or if the scan tool and ABS ECU
cannot communicate, there is a good possibilit
y
that power is not flowing to the ECU.
Caution
l If there is no output of diagnostic trouble
codes, there is a good possibility that the
fail safe is functioning.
J/B
IGNITION
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i
CD10A
728
Is there on-board diagnostic No )output? (Is there communi-cation with scan tool?) CONTINUE TONEXT PAGE
Yes
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Does the ABS warning light
remain illuminated
even
with the ECU connector dis-
connected?
YesNoShort in ECU transistor
1 Replace ECU.I

MAIN FUSIBLE
LINK @
SERVICE BRAKES - Anti-lock Braking System Troubleshooting35-33
E-6When diagnostic trouble code “52 MOTOR RLY” is displayed
[Explanation][Hint]
The ABS ECU outputs this diagnostic trouble code forIf there is motor operation noise when wheel speed
the motor relay and motor in the following cases.
exceeds Gkm/h (4mph) when starting up after the
l When the motor relay does not function
engine is started, or when there is forced scan tool
lWhen there is trouble with the motor itself and itdrive, there is a broken or short circuited motor
does not revolve
monitor wire.
lWhen the motor ground line is disconnected and
the motor does not revolve
l When the motor continues to revolve Does the motor make a
YesBroken wire or short cir-noise when wheel speed)
1
cuit in motor monitor line
exceeds 6 km/h (4 mph) or1
[ 1 ,2
/ 3 14 15 I6 1 I 18 I9l10l11112113114115116117l1sJ~l9~0~1~2tz3l2~~25t6~27~2~29~~~31~32b3134135/
14A0684
L
Remove the motor relay andcheck resistance values.No. 85-No. 86:resistancevalue 30-60 9No. 30-No. 87: no continui-
Motor relay malfunction
4
Replace motor relay.I
tYBattery voltage is applied onterminals No.85 and No.86grounded.No. 30-No. 87: continuity
Yes
Is pump motor ground con-netted normally? Connect ground wire.
\/i
Does voltage between bodyBroken wire in pump
connector terminal 11 andNo *motor power circuit
ground indicate battery vol-
tage?
1
Repair the harness.
Yes
Connect the HU
tonnetor and remove theECUconnector.
I
Is resistance between bodyNo - Malfunction of harness
connector terminal No. 2 and- between HU and ECU No.26 30-60 ohms?
1 Yes
Is resistance between ECUharness side connector ter- NO
minal No. 5 and ground 0.1 -0.3 ohm?
Yes
ABS ECU malfunction
1 TSB Revision
Replace ABS ECU.

35-34SERVICE BRAKES - Anti-lock Braking System Troubleshooting
TROUBLESHOOTING (ABS-AWD)
Confirm condition in the following way and diagnose accordingly.
c
P
t:
1
-)oes
the ABS warning light illuminate as described
elow up to the time the engine starts?
1) When the ignition key is turned to the “ON”
position, the ABS warning light blinks four times
for approximately
1 second due to the ABS ECU
(as a self check of the valve relays is performed),
and goes out and stays out.
2) W
ith the ignition key in the “START” position,
power to the ABS ECU is interrupted and the ABS warning light remains lit because the valve
relay is OFF.
(3) When the ignition key is turned from the “START’ position to the “ON” position, the ABS warning
light blinks four times for approximately
1
second (during this time a recheck of the valve
relays is performed), and then goes out and
stays out.
,,,\~~\l’l”“F’,r//,,,l/,,
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x 1000
rimonUILEAED nxL GNL”Oyg@O@~ 2F
ABS
warnmg’l~ght66A0093
ABS warning
lightONI
OFF
Ignitionkey
ACC, LOCK
114AO594
YesCONTINUE TO NEXT PAGENo
1
No.Trouble condition
ABS warning light does not light up at all.
1
ABSwarning
light
Ignition
keyACC, ON
OFFLOCK 1
I
When the lgnltlon
key IS turned to the
“ON” position, it remains lighted.
ABS warnina
ON , l Short in ECU warning light drive circuit
l Malfunction of ECU
-“l-l- -III
ignitionkey
ACC. LO!?-14AO591
Major causes
l ABS warning light bulb is burnt out.
l Open in ABS warning light electrical circuit (check for blown fuse)
l Fail safe is functioning due to ECU on-
board diagnostic
Does not illuminate when ignition key is
in “START” position. l Malfunction of valve relay
l Break in harness between ABS warn-
ing light and HU
l Break in harness between HU and
14AO595
Remedy
Check, using flow
chart A (Refer to
P.35-39.)
Check, using flow
chart B (Refer toP.35-42.)
1 2 /light
-
Check, using flow
chart C (Refer to
P.35-44.)
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SERVICE BRAKES - Anti-lock Braking System Troubleshooting
W
ith the ignition key in the “ON” posi- No
Check fuse No. 9. If it is
tion, do other warning lights illuminate? blown, correct the cause of
-T-
Yesthe blown fuse and then
replace the fuse.I
Remove the combination
meter, and check with
the ignition key “ON”.
I
Does voltage between har-NoThe harness between the ness
connector terminal
No. 8 and ground indicate
-combination meter from
fuse No. 9 is broken.
battery voltage?
I
Yes Repair harness.
Circuit in combination meter
is broken.
L Repair or replace com-
bination meter.
Turn the ignition switch OFF an
check.
I
Is the ABS warning light normal? (CheckNo
for burned bulb.)c A$Eedyrning light bulb
,
c Replace ABS warning
light bulb.
Yes
Is there continuity between terminals No. No -
8 and 4” or 17’2 on the combinationI Malfunction of combinatio
n
meter
I Repair or replace combi-
meter side? nation meter
Are instrument panel wiring harness, No
-~
engine compartment wiring harness, . Connect connectors firmly.
body wiring harness and ABS wiring
(Check for pins pulled out or
harness connectors connected properly? bent, repair as needed.)
I
1 Yes
I
Broken wire in ECU, valve relay or both
drive circuits. Check and repair both
circuits.
I
NOTE‘1: Non-Turbo . Turbol *:Non-Turbo
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35-42
SERVICE BRAKES - Anti-lock Braking System Troubleshooting
BABS warning light illuminated after the engine is started and remains on\
.
[Explanation]
This is the symptom when the ABS ECU does not
power up due to broken ECU power circuit, etc.,
when the fail safe function operates and isolates the
system or when the warning light drive circuit is
short circuited.
[Hint]
Check the on-board diagnostic output and if there is
no output voltage or if the scan tool and ABS ECU
cannot communicate, there is a good possibility
that power is not flowing to the ECU.
Caution
l
If there is no output of diagnostic trouble
codes, there is a good possibility that the
fail safe is functioning.
MAINFUSIBLELINK @
IGNITION
SWITCH
(IG1)
ILOIE;NATION
+10
3
@izJ”,HUZ8 p:r12 /e-,
xx
I
I
I*I
; 16 4=
9
II
d
+qfimamq!2 a
I -LQ-7 ABS ECUm1
: Non-Turbo . Turbo: Non-Turbo Is there on-board diagnosticNocCONTINUE TO
output? (Is there communi- NEXT PAGE
cation with scan tool?)
I
Yes
Does diagnostic troublecode output display normalcodes?
No . Check, using the diagnos-tic trouble code checkchart. (Refer to P.35-38.)IIILI
Short in harness betweenrgl;r ECU and ABS warning) Repair harness or replacecombination meter.
II
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