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/InstallationValve Clearance Inspection
NOTE
Valve clearance must be checked and adjusted when
the engine is cold (at room temperature).
Remove:
Crankshaft Sensor Cover (see Crankshaft Sensor Removal
in the Electrical System chapter)
Cylinder Head Cover (see Cylinder Head Cover Removal
in the Engine Top End chapter)
Turn t ...
Hub Bearing Inspection
Since the hub bearings are made to extremely close tolerances,
the clearance can not normally be measured.
NOTE
Do not remove any bearings for inspection. If any bearings
are removed, they will need to be replaced with
new ones.
Turn each bearing in the hub back and forth [A] while
checki ...
Stick Coil Inspection
Remove the stick coils (see Stick Coil Removal).
Measure the primary winding resistance [A] as follows.
Connect the hand tester between the coil terminals.
Set the tester to the × 1 Ω range, and read the tester.
Measure the secondary winding resistance [B] as follows.
Conn ...