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 InspectionAir Switching Valve Installation
Install the air switching valve [A] with hose [B] as shown
in the figure.
Front [C]
Left Side View [D]
White Paint [E]
Air Switching Valve Operation Test
Refer to the Air Suction System Damage Inspection in the
Periodic Maintenance chapter.
Air Switching Valve Unit Test ...
Coolant Reserve Tank Installation
Install the following to the coolant reserve tank [A].
Pad [B]
Gasket [C]
Cap [D]
Collar [E]
Install the coolant reserve tank and tighten the bolt [F].
Run the hoses correctly (see Cable,Wire, and Hose Routing
section in the Appendix chapter).
Fill the coolant reserve tank with ...
Front Seat Installation
Installation is the reverse of removal. Note the following.
Check that the dampers [A] are in place on the front seat.
Install the collars [B] as shown in the figure.
Place the seat hooks [A] under the fuel tank bracket [B].
...