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/InstallationCrankshaft Sensor Removal
Remove:
Fuel Tank (see Fuel Tank Removal in the Fuel System
(DFI) chapter)
Crankshaft Sensor Lead Connector [A]
Remove:
Right Lower Fairing (see Lower Fairing Removal in the
Frame chapter)
Bolts [A]
Crankshaft Sensor Cover [B] and Gasket
Oil Pressure Switch Terminal [C]
...
Check 3-6: Neutral Indicator Light (LED) Inspection
Connect the leads in the same circuit as Check 3-2.
Connect the terminal [8] to the battery (–) terminal.
Check that the neutral indicator light (LED) [A] goes on.
If the indicator light does not go on, replace the meter unit.
...
Cylinder Compression Measurement
NOTE
Use the battery which is fully charged.
Warm up the engine thoroughly.
Stop the engine.
Remove the spark plugs (see Spark Plug Replacement in
the Periodic Maintenance chapter).
Attach the compression gauge [A] and adapter [B] firmly
into the spark plug hole.
Using the startermo ...