Air Switching Valve Removal/Installation
Air Switching Valve Inspection
If the air switching valve [A] is normal, check the wiring for continuity (see Air Switching Valve Circuit).
Special Tool - Hand Tester: 57001-1394
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).

Air Switching Valve Circuit

1. ECU
2. Air Switching Valve
3. Ignition Switch
4. Joint Connector F
5. Joint Connector A
6. Fuse Box 1
7. Ignition Fuse 15 A
8. Relay Box
9. ECU Main Relay
10. Frame Ground 1
11. Frame Ground 3
12. Starter Relay
13. ECU Fuse 15 A
14. Main Fuse 30 A
15. Battery
16. Engine Ground
Exhaust Butterfly Valve Actuator 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 ...
Oil Pressure Relief Valve Inspection
Remove the oil pressure relief valve (see Oil Pressure
Relief Valve Removal).
Check to see if the valve [A] slides smoothly when pushing
it in with a wooden or other soft rod, and see if it comes
back to its seat by spring [B] pressure.
NOTE
Inspect the valve in its assembled stat ...
Fuel Pump Operating Voltage Inspection
NOTE
Be sure the battery is fully charged.
Turn the ignition switch to OFF.
Remove:
Fuel Tank Bolts (see Fuel Tank Removal)
Fuel Tank Bracket Bolts (see Fuel Tank Removal)
Disconnect the fuel pump lead connector and connect the
harness adapter [A] between these connectors as shown
i ...