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 InspectionSpark Plug Condition Inspection
Remove the spark plugs (see Spark Plug Replacement in
the Periodic Maintenance chapter).
Visually inspect the spark plugs.
If the spark plug center electrode [A] and/or side electrode
[B] are corroded or damaged, or if the insulator [C]
is cracked, replace the plug.
If the spark plug is ...
Water Temperature Sensor Output Voltage Inspection
NOTE
Be sure the battery is fully charged.
Turn the ignition switch to OFF.
Remove the throttle body assy (see Throttle Body Assy
Removal in the Fuel System (DFI) chapter).
Disconnect the water temperature sensor connector and
connect the measuring adapter [A] between these connectors
...
For 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 ...