1989 MITSUBISHI GALANT warning

35-68SERVICE BRAKES - Service Adjustment Procedures
A.B.S. warning light
Ignition switch
sT;!i;%
lARD175
Filter4
kR
14A0171
ANTI-LOCK BRAKING SYSTEM (A.B.S.) CHECK
(CHECKING BY THE A.B.S. WARNING LIGHT)
M35FOAK
By following the procedures described below, check whether
the system is good or not by checking the illumination and non-illumination of the A.B.S. warning light.
(1) Check to be sure that the A.B.S. warning light illuminates
when the ignition key is turned to the ON position, and
that it again illuminates two times during a short period of
time (approximately 0.5 second) after the engine is started, and that it then stops illumination.
(2) After checking that the A.B.S. warning light does not illuminate during a period of approximately 2 minutes
while the engine is left idling, test drive at a vehicle
speed of approximately 30 km/h (18.6 mph) or more for
about 30 seconds or longer and check that the A.B.S.
warning light does not illuminate during that time.
(3) If any abnormal condition is discovered during steps (1) and (2) above, check the system by following the anti-
skid brake system troubleshooting procedures.
Caution
Before checking the anti-lock braking system by the
A.B.S. warning light as described above, first check
the ordinary brake system that there are no problems
such as leakage of the brake fluid, incorrect connec-
tions of the brake tubes, etc.
WHEEL SPEED SENSOR OUTPUT VOLTAGE
CHECK
M3sFoAE
(1) Jack up the vehicle and release the parking brake.
(2) Disconnect the electronic control unit harness connector,
and measure the speed sensor output voltage at the
vehicle side harness connector.
(3) Rotate the wheel to be measured at a speed of about
one-
half to one rotation per second and while doing S
O
measure the speed sensor output voltage by using a
voltmeter or oscilloscope.
(4) If an oscilloscope is used, use the filter shown in the
figure at the left.
Speed sensor1-1 Standard value
1 Front left15-4 (22-4 I50 mV or more 1IIIII
IFront rightI1 23-21 1 23-21 1IIIII1 Rear right1 24-26 1 24-26 1II IIIIII Rear left( 7-9 18-9 1IIII1
NOTE
1. A voltmeter with AC mV range indication should be used
for measurement.
2. When disconnecting the adaptor from the body harness connector, attach a cord to the male connector and then
pull to disconnect.
TSB Revision

35-70SERVICE BRAKES- Service Adjustment Procedures
I, ! I ! I4 IO II IIWhen turned manually :---;---i-.-l---L--.I 8 ! IaI 1 11 1 II ’I 1’ I I I;-;--1---:--‘---+---t---i ’I IL---)-.-i---+--.II ’ I I 1 , 1 ,I
--:--~---;---:---~--~--
POINTS IN WAVEFORM MEASUREMENT
3. Manually turning the wheel to be measured by
l/2 to 1
turn/second, measure the output voltage with a circuit
tester or oscilloscope. Output voltage: When measured with circuit tester: 70
mV or more
When measured with oscilloscope (max. voltage): 100
mV or more
Probable causes of low output voltage
0 Speed sensor pole piece-to-rotor clearance too large
l Faulty speed sensor
4. Then, in order to observe the output state of the wheel
speed sensors, shift into low gear
(AWD vehicle) and drive
the wheels, observe the output voltage waveform of each
wheel speed sensor with an oscilloscope.
In the case of the FWD vehicle, observe the waveform with
an oscilloscope; for the front wheels, shift into low gear and
drive the wheels; for the rear wheels, turn the wheels manually at a constant speed.
NOTE
1.Waveform may also be observed by actually driving the
vehicle.
2.The output voltage is low when the wheel speed is low
and increases as the wheel speed increases.
Symptom
Too small or zero waveform amplitude Probable causes
Faulty wheel speed sensor Remedy
Replace sensor
Incorrect pole piece-to-rotor clearanceAdjust clearance
Waveform amplitude fluctuates Axle hub eccentric or with large runoutReplace hub
excessively (this is no problem if
the minimum amplitude is 100 mVor more)
Noisy or disturbed waveformOpen circuit in sensor Replace
sensor
Open circuit in harness
Correct harness
Incorrectly mounted wheel speed sensorMount correctly
Rotor with missing or damaged teeth Replace rotor
NOTEThe wheel speed sensor cable moves following motion of the front or rear\
suspension. Therefore, it is likely that it
has anopen circuit only when driving on rough roads and it functions normally \
on ordinan/ roads. It is, therefore, recommended
to observe sensor output voltage waveform also under special conditions,\
such as rough road dnvlng.
TSB Revision
INSPECTION OF HYDRAULIC UNIT
INSPECTION BY FEEL
(1) Jack up the vehicle and support the vehicle with rigid racks
placed at the specified jack-up points.
(2) Release the parking brake and determine the drag force(drag torque) of each wheel by feel.
(3) Set the scan tool through the adapter harness
(MB991 377)
as illustrated.
(4) After confirming that the shift lever or selector lever is in the neutral position, start the engine.
The ABS warning light lights up, it goes into the scan tool mode. In the scan tool mode, ABS does not function.
I

35-72SERVICE BRAKES - Service Adjustment Procedures
14AO701 1
INSPECTION BY USING BRAKE FORCE TESTER
NOTE
(1) The brake force tester roller and tire must be dry during thetest.
(2) When testing the front brakes, apply the parking brake and when testing the rear brakes, apply chocks to the front
wheels to lock them.
(1) Place the front or rear wheels on the brake force tester
(2) &(%:he
scan tool through the adapter harness (MB991377)
as illustrated.
(3) After confirming that the shift lever or selector lever is in
the neutral position, start the engine.(The ABS warning light lights up, it goes into the scan tool
mode. In the scan tool mode, ABS does not function.)
(4) Operate the brake force tester roller.
(5) Depress the brake pedal until the brake force tester
indicates the following value and keep the brake force at
this level during the test.
Front wheels: 800- 1 ,OOON (176 - 220 Ibs.)
Rear wheels: 600
- 800N (132 - 176 Ibs.)
(6) Allow the brake tester indication to stabilize before operat-
ing the scan tool to perform actuator test (Item
No.01, 02,
03). Then, read change of tester indication. Referring to the following “Judgement in Inspection by
Using Brake Force Tester” table, judge and take corrective
action if necessary.
NOTE
While the ABS is in the fail safe mode, the scan tOOf actua-
tor test cannot be made.
TSB Revision

SERVICE BRAKES -Service Adjustment Procedures35-75
14AO197
FLAT BATTERY REMEDYM35FOAF
When booster cables are used to start the engine when the
battery is completely flat and then the vehicle is immediately
driven without waiting for the battery to recharge itself to
some extent, the engine may misfire, and driving might not be
possible. This happens because A.B.S. consumes a great
amount of current for its self-check function; the remedy is to
either allow the battery to recharge sufficiently, or to remove
the fuse for A.B.S. circuit, thus disabling A.B.S.
The A.B.S. warning light will illuminate when the main fusible
link (for A.B.S.) is removed.
After the battery has sufficiently charged, install the main
fusible link (for A.B.S.) and restart the engine; then check to be
sure the A.B.S. warning light is not illuminated.
TSB Revision
BRAKE FLUID PRESSURE SWITCH CHECK
hl35FOAL
(1) Disconnect the hydraulic pressure switch connector.
(2) Check the continuity between the terminals of hydraulic pressure switch.
Condition Between terminals
Brake pedal not depressed
No conductance
Brake pedal depressed lightlyNo conductance
Brake pedal depressed
stronglyConductance