If the radiator fan relay is normal, check the wiring for continuity, using the wiring diagram in this section.
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).
Radiator Fan Circuit

1. ECU
2. Fan Motor
3. Ignition Switch
4. Joint Connector F
5. Fuse Box 1
6. Ignition Fuse 15 A
7. Relay Box
8. Fan Relay
9. Frame Ground 3
10. Fuse Box 2
11. Fan Fuse 15 A
12. Starter Relay
13. Main Fuse 30 A
14. Battery
15. Engine Ground
Radiator Fan Relay Removal/InstallationSubthrottle Valve Actuator Resistance Inspection
Turn the ignition switch to OFF.
Disconnect the subthrottle valve actuator connector [A].
Connect a digital meter to the subthrottle valve actuator
connector [A].
Measure the subthrottle valve actuator resistance.
Subthrottle Valve Actuator Resistance
Connections: Y/BK lead [1 ...
ESD Actuator Resistance Inspection
Turn the ignition switch to OFF.
Remove the electronic steering damper unit (see Steering
Damper Removal in the Steering chapter).
Connect a digitalmeter to the ESD actuator connector [A].
Measure the ESD actuator resistance.
ESD Actuator Resistance
Connections: BK lead [1] ← ...
System Components
1. FI ECU
The FI ECU analyzes the motorcycle conditions based
on the signals from the front/rear wheel rotation sensors
and FI sensors (such as the crankshaft sensor and main
throttle sensor), and controls engine power by reducing the
number of ignition and retarding the ignition timing. The
m ...