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 InspectionFor Primary Fuel Injectors
Remove the air cleaner housing (see Air Cleaner Housing
Removal).
Disconnect the primary fuel injector connector [A].
Connect a digital meter to the terminals in each primary
fuel injector [A].
Measure the primary fuel injector resistance.
Primary Fuel Injector Resistance ...
Parts Location
1. Timing Rotor
2. Crankshaft Sensor
3. Horn
4. Oil Pressure Switch
5. Rear Brake Light Switch
6. Oxygen Sensor (Equipped Models)
7. Alternator
8. Stator Coil
9. Gear Position Switch
10. Sidestand Switch
11. Immobilizer Amplifier (Equipped Models)
12. Radiator Fan Motor
1 ...
Camshaft Chain Tensioner Removal
NOTICE
This is a non-return type camshaft chain tensioner.
The push rod does not return to its original position
once it moves out to take up camshaft chain slack.
Observe all the rules listed below.
When removing the tensioner, do not take out the
mounting bolts only halfway. Retighteni ...