Anti-Lock Braking System (Abs) Check; Wheel Speed Sensor Output Voltage Check - Mitsubishi 1989-1993 GALANT Service Manual

SERVICE BRAKES - Service Adjustment Procedures
warning light
A.B.S.
Ignition switch
Filter
4 kR
ANTI-LOCK BRAKING SYSTEM (A.B.S.) CHECK
(CHECKING BY THE A.B.S. WARNING LIGHT)
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.
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 <Up to 1991 models>
(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
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 sensor
Front right
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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
23-21 23-21
24-26 24-26
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