NOTICE
Never drop the air switching valve especially on a hard surface. Such a shock to the air switching valve can damaged it.

Air Suction Valve Inspection
Air Switching Valve InstallationLower Crankcase Assembly
Install the ball bearing [A] and the oil level inspection window
[B] until they are bottomed
Apply soap and water solution to the oil level inspection
window before installation.
Install the new circlip [C].
Apply a non-permanent locking agent to the oil passage
plug [D].
Tighten: ...
Crankshaft Sensor Peak Voltage Inspection
NOTE
Be sure the battery is fully charged.
Using the peak voltage adapter [A] is more reliable way
to determine the condition of the crankshaft sensor than
crankshaft sensor internal resistance measurements.
Disconnect the crankshaft sensor lead connector (see
Crankshaft Sensor ...
ECU Power Supply Inspection
Remove the upper air cleaner housing (see Air Cleaner
Element Replacement in the Periodic Maintenance chapter).
Visually inspect the ECU connectors.
If the connector is clogged with mud or dust, blow it off
with compressed air.
Remove the ECU (see ECU Removal).
Visually inspect the ...