NOTE
Be sure the battery is fully charged.
Main Harness [B] Vehicle-down Sensor [C]
Special Tool - Measuring Adapter: 57001-1700

Vehicle-down Sensor Input Voltage Connections to Adapter: Digital Meter (+) → R (sensor BL) lead Digital Meter (–) → BK (sensor BR/BK) lead

Input Voltage
Standard: DC 4.75
5.25 V
If the reading is within the standard, check the output voltage (see Vehicle-down Sensor Output Voltage Inspection).
If the reading is out of the standard, remove the ECU and check the wiring for continuity between main harness connectors.
Special Tool - Hand Tester: 57001-1394
Disconnect the ECU and sensor connectors.
Wiring Continuity Inspection ECU Connector [A] ←→ Vehicle-down Sensor Connector [B] BL lead (ECU terminal 9) [C] BR/BK lead (ECU terminal 13) [D]

If the wiring is good, check the ECU for its ground and power supply (see ECU Power Supply Inspection in the Fuel System (DFI) chapter).
If the ground and power supply are good, replace the ECU (see ECU Removal/Installation in the Fuel System (DFI) chapter).
Vehicle-down Sensor Installation
Vehicle-down Sensor Output Voltage InspectionCable Removal
Remove:
Air Cleaner Housing (see Air Cleaner Housing Removal
in the Fuel System (DFI) chapter)
Right Lower Fairing (see Lower Fairing Removal in the
Frame chapter)
Loosen the nuts [A], and slide the lower end of the clutch
cable to give the cable plenty of play.
Screw in the ...
Radiator Hose and Pipe Inspection (coolant leak, damage, installation
condition)
The high pressure inside the radiator hose can cause
coolant to leak [A] or the hose to burst if the line is not
properly maintained.
Visually inspect the hoses for signs of deterioration.
Squeeze the hoses. A hose should not be hard and
brittle, nor should it be soft or swollen.
Repl ...
Steering Stem Bearing Lubrication
Remove the steering stem (see Stem, Stem Bearing Removal
in the Steering chapter).
Using a high flash-point solvent, wash the upper and
lower ball bearings [A] in the cages.
Wipe the upper and lower outer races which are press
-fitted into the head pipe to clean off grease and dirt.
V ...