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/InstallationKIBS Hydraulic Unit Inspection
Remove the KIBS hydraulic unit (see KIBS Hydraulic Unit
Removal).
Visually inspect the connector terminals [A].
Replace the KIBS hydraulic unit or main harness if either
of the terminals are cracked, bent, or otherwise damaged.
If the KIBS hydraulic unit connector is clogged with mud
or ...
ECU Communication Error (Service Code 39)
ECU Communication Line Inspection
When the data is not sent from the ECU to the meter unit
for more than about 10 seconds, the service code 39 is
displayed.
The data is sent through the CAN communication line.
The service code 39 is detected with the meter unit.
When the user mode, this commun ...
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 ...