If the fuse is good, check the wiring continuity as follows.
Disconnect: Battery Positive Cable (see Battery Removal in the Electrical System chapter) KIBS Hydraulic Unit Lead Connector (see KIBS Hydraulic Unit Removal in the Brakes chapter)

Check the wiring continuity between the positive cable terminal [A] of the battery and R/W lead terminal [B] in the KIBS Hydraulic Unit Lead Connector [C].
If the wiring is open, replace or repair the harness (see KIBS System Circuit in the Brakes chapter).
If the wiring is good, go to next step.

The KIBS motor relay is built in the KIBS Hydraulic Unit.
Therefore the relay cannot be checked directly.
If this service code appears even if all checks are ended, replace the KIBS hydraulic unit.
If the service code does not appear, the KIBS system normal (temporary failure).
Front, Rear Wheel Rotation Difference Abnormal Inspection (Service Code b
25)
Front Wheel Rotation Sensor Signal Abnormal (Service Code b 42)Clutch Cover Assembly
Replace the needle bearings and oil seal with new ones.
NOTE
Install the needle bearings so that the manufacture’s
mark face out.
Install the needle bearings [A] and oil seal [B] position as
shown in the figure.
Press the upper and lower bearings so that the bearing
surface [ ...
Engine Sprocket Installation
Replace the sprocket washer and axle cotter pin.
Install the engine sprocket onto the output shaft.
Apply molybdenum disulfide oil solution to the threads
and seating surface of the engine sprocket nut.
Tighten:
Torque - Engine Sprocket Nut: 145 N·m (14.8 kgf·m, 107
ft·lb)
NOTE
...
Air Suction Valve Installation
Install the air suction valve so that opening [A] of the reed
faces downward.
Apply a non-permanent locking agent to the threads of
the air suction valve cover bolts [A], and tighten them.
Torque - Air Suction Valve Cover Bolts: 9.8 N·m (1.0 kgf·m,
87 in·lb)
...