ABS <4WD> -
Troubleshooting
35B-5
(2) For road surfaces such as snow-covered roads and gravel roads, the braking distance for vehicles
with ABS can sometimes be longer than that for other vehicles. Accordingly, advise the customer
to drive safely on such roads by lowering the vehicle speed and not being too overconfident.
(3) Diagnosis detection conditions vary according to the diagnosis code. When re-checking trouble
symptoms, the conditions given in the “Explanation” column of the Inspection Chart Classified by
Trouble Symptoms must always be satisfied.
ABS WARNING LAMP INSPECTION
Check that the ABS warning lamp illuminates in the following
way.
Even if the pressure inside the accumulator of the hydraulic
brake booster (HBB) is below the specified value, the ABS
warning lamp will illuminate because ABS operation has been
stopped. In such cases, if the HBB pump is driven by the
accumulated pressure inside the accumulator a n d causes
the ABS warning lamp to switch off, it does not indicate a
system malfunction.
(1) When the ignition switch is turned to the ON position,
the ABS warning lamp illuminates* for approximately 3
seconds, and then switches off.
(2) When the ignition switch is turned to the START position,
the ABS warning lamp remains illuminated.
(3) When th e ignition switch returns from the START to the
ON position, t he ABS warning lamp illuminates* for
approximately 3 seconds, and then remains switched off.
(4) If any of the above do not occur, check the diagnosis
codes.
NOTE
*: The ABS warning lamp may remain illuminated after t he
ignition switch is turned to the ON position and the vehicle
starts moving until the vehicle speed reaches a speed
of several km/h. This only occurs if a diagnosis code
from No. 21 to No. 24 relating to a wheel speed sensor
malfunction was generate when the ignition switch was
last turned to the ON position and is still stored in the
ABS-ECU. The ABS-ECU will cause the ABS warning
lamp to illuminate until the point where it can ascertain
(during the starting-off check) that the problem associated
with this diagnosis code has returned to normal.
DIAGNOSIS FUNCTION
READING DIAGNOSIS CODES
Use the MUT-
II
or the ABS warning lamp to read the diagnosis
codes.
(Refer to GROUP 00 - How to Use Troubleshooting/Inspection
Service Points.)
NOTE
Connect the MUT-
II
to the 16-pin diagnosis connector.
ABS warning lamp
Approx. 3 s
Approx. 3 s
ABS warn-
ing lamp
On
Off
Ignition
switch
START
ON
ACC,
LOCK
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