Disconnect the main throttle sensor connector and connect the setting adapter [A] between these connectors.

Special Tool - Throttle Sensor Setting Adapter: 57001 -1538
Main Throttle Sensor Output Voltage Connections to Adapter: Digital Meter (+) → R (sensor V/W) lead
Digital Meter (–) → BK (sensor BR/BK) lead
Install the following parts temporarily.
Throttle Body Assy (see Throttle Body Assy Installation in the Fuel System (DFI) chapter) Air Cleaner Housing (see Air Cleaner Housing Installation in the Fuel System (DFI) chapter) Fuel Tank (see Fuel Tank Installation in the Fuel System (DFI) chapter)
Throttle Sensor Setting Adapter [A]
Idle Speed Standard: 1 100 ±50 r/min (rpm)

Output Voltage
Standard: DC 0.64
0.68 V at idle
throttle opening
DC 3.89
4.09 V at full throttle
opening (for
reference)
NOTE
Example: In the case of a input voltage of 4.75 V.
0.64 × 4.75 ÷ 5.00 = 0.61 V
0.68 × 4.75 ÷ 5.00 = 0.65 V
Thus, the valid range is 0.61
0.65 V
If the reading is out of the standard, replace the throttle body assy.
If the reading is within the standard, remove the ECU and check the wiring for continuity between harness connectors.
Special Tool - Hand Tester: 57001-1394
Disconnect the ECU and sensor connectors.

Wiring Continuity Inspection ECU Connector [A] ←→ Main Throttle Sensor Connector [B] V/W lead (ECU terminal 25) [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).
Main Throttle Sensor Circuit

1. ECU
2. Subthrottle Sensor
3. Main Throttle Sensor
Main Throttle Sensor Resistance InspectionCrankcase Halves Assembly
Install:
Crankshaft (see Crankshaft Installation)
Connecting Rods (see Connecting Rod Installation)
Using a cleaning fluid, clean off any oil or dirt on the mating
surface of the crankcase halves.
Apply liquid gasket to the mating surface of the lower
crankcase half as shown in the fi ...
Radiator and Cooling Fan
Check the radiator fins for obstruction
by insects or mud. Clean off
any obstructions with a stream of
low-pressure water.
WARNINGThe cooling fan spins at high
speed and can cause serious
injuries. Keep your hands and
clothing away from the cooling
fan blades at all times.
...
Clutch Plate Warp Inspection
Place each friction plate or steel plate on a surface plate
and measure the gap between the surface plate [A] and
each friction plate or steel plate [B] with a thickness gauge
[C]. The gap is the amount of friction or steel plate warp.
If any plate is warped over the service limit, repla ...