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/InstallationStick 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 ...
KIBS Hydraulic Unit Removal
NOTICE
The KIBS hydraulic unit [A] has been adjusted
and set with precision at the factory. Therefore, it
should be handled carefully, never struck sharply,
as with a hammer, or allowed to fall on a hard
surface.
Be careful not to get water or mud on the KIBS hydraulic
unit.
Drain the b ...
Troubleshooting Guide
NOTE
Refer to the Fuel System chapter for most
of DFI trouble shooting guide.
This is not an exhaustive list, giving every
possible cause for each problem listed. It
is meant simply as a rough guide to assist
the troubleshooting for some of the more
common difficulties.
Engine Doe ...