Workshop Manual

5A–12
BRAKE CONTROL SYSTEM
circuit. The symptom diagnosis chart may also be useful
in isolating the failure. Most intermittent problems are
caused by faulty electrical connections or wiring. When
an intermittent failure is encountered, check suspected
circuits for damage:
B Suspected harness damage.
B Poor mating of connector halves or terminals not fully
seated in the connector body (backed out).
B Improperly formed or damaged terminals.
Test Driving ABS Complaint Vehicles
In case of an intermittent ABS lamp illumination, see
“Diagnosis by ABS Warning Light illumination Pattern” or
go to 5A–37. In some cases, the vehicle may need to be
test driven by following the test procedure below.
1.Start the engine and make sure that the “ABS” W/L
goes OFF. If the W/L remains ON, it means that the
Diagnostic Trouble Code (DTC) is stored. Therefore,
read the code and locate the fault.
NOTE: The DTC cannot be cleared if the vehicle speed
does not exceed 12 km/h (8 mph) at DTC, even though
the repair operation is completed.
2.Start the vehicle and accelerate to about 30 km/h (19
mph) or more.
3.Slowly brake and stop the vehicle completely.
4.Then restart the vehicle and accelerate to about 40
km/h (25 mph) or more.
5.Brake at a time so as to actuate the ABS and stop the
vehicle.
6.Be cautious of abnormality during the test. If the W/L
is actuated while driving, read the DTC and locate the
fault.
7.If the abnormality is not reproduced by the test, make
best efforts to reproduce the situation reported by the
customer.
8.If the abnormality has been detected, repair in
accordance with the “SYMPTOM DIAGNOSIS” .
NOTE:
B Be sure to give a test drive on a wide, even road with a
small traffic.
B If an abnormality is detected, be sure to suspend the
test and start trouble diagnosis at once.
“ABS” Warning Light
When ABS trouble occurs to actuate “ABS” warning light,
the trouble code corresponding to the trouble is stored in
the EHCU. Only ordinary brake is available with ABS
being unactuated. Even when “ABS” warning light is
actuated, if the starter switch is set ON after setting it OFF
once, the EHCU checks up on the entire system and, if
there is no abnormality, judges ABS to work currently and
the warning light is lit normally even though the trouble
code is stored.
NOTE: Illumination of the “ABS” warning light indicates
that anti-lock braking is no longer available. Power
assisted braking without anti-lock control is still available.
Normal Operation
“ABS” Warning Light
When the ignition is first moved from “OFF” to “RUN” , the
amber “ABS” warning light will turn “ON” . The “ABS”
warning light will turn “ON” during engine starting and will
usually stay “ON” for approximately three seconds after
the ignition switch is returned to the “ON” position. The
warning light should remain “OFF” at all other times.