If this service code appears, check that the following parts are correctly.
Crankshaft Sensor Gear Position Switch Starter Lockout Switch Main Throttle Sensor Rear Wheel Rotation Sensor
If these parts are normal, check the ESD ECU for its ground and power supply (see ESD ECU Power Supply Inspection).
ESD ECU Removal
ESD ECU Installation
Refer to the ESD (Electronic Steering Damper) ECU Installation in the Steering chapter.
ESD ECU Power Supply Inspection

If the connector is clogged with mud or dust, blow it off with compressed air.
If the terminals of the main harness connector are damaged, replace the main harness.
If the terminals of the ESD ECU connectors are damaged, replace the ESD ECU.
Special Tool - Hand Tester: 57001-1394

ESD ECU Grounding Inspection Connections: (I) BK/Y lead (ESD ECU terminal 9) ←→ Battery (–) Terminal (II) Engine Ground ←→ Battery (–) Terminal Criteria: Both: 0 Ω
If no continuity, check the connector, the engine ground lead, or main harness, and repair or replace them if necessary.
If the wiring is good, check the power source voltage of the ESD ECU.
NOTE
Be sure the battery is fully charged.

Special Tool - Needle Adapter Set: 57001-1457
ESD ECU Power Supply Inspection Connections:
(I) Digital Meter (+) → Terminal 18 (BR/BK) Digital Meter (–) → Battery (–) terminal
Ignition Switch OFF: 0 V
Ignition Switch ON: Battery Voltage
If the reading is out of the specification, check the following.
Main Fuse 30 A (see Fuse Inspection in the Electrical System chapter) Electronic Steering Damper Fuse 10 A (see Fuse Inspection in the Electrical System chapter) Power Source Wiring (see wiring diagram in this section)
If the fuse and wiring are good, replace the ESD ECU (see ESD (Electronic Steering Damper) ECU Removal/Installation in the Steering chapter).
ESD ECU Power Source Circuit

1. Ignition Switch
2. ESD ECU
3. Engine Ground
4. Battery
5. Starter Relay
6. Main Fuse 30 A
7. Frame Ground 3
8. Fuse Box 1
9. ESD Fuse 10 A
ESD Actuator Input Voltage InspectionIntake Air Pressure Sensor #2 Installation
NOTE
The intake air pressure sensor #2 is the same part as
the intake air pressure sensor #1.
Installation is basically the reverse of removal.
Position the intake air pressure sensor #2 [A] between the
projections [B] on the rubber damper.
Install the rubber damper [A] on the brac ...
Gear Position Switch Removal
Remove:
Oil Pump (see Oil pump Removal in the Engine Lubrication
System chapter)
Engine Sprocket (see Engine Sprocket Removal in the
Final Drive chapter)
Fuel Tank (see Fuel Tank Removal in the Fuel System
(DFI) chapter)
Disconnect the connector [A].
Remove:
Screws [A]
...
Valve-to-Guide Clearance Measurement (Wobble Method)
If a small bore gauge is not available, inspect the valve
guide wear by measuring the valve to valve guide clearance
with the wobble method as indicated below.
Insert a new valve [A] into the guide [B] and set a dial
gauge against the stem perpendicular to it as close as
possible to the cy ...