If the fuel pump relay is normal, check the wiring to the fuel pump relay (see Fuel Pump Relay Circuit).
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).
Fuel Pump Relay Circuit

1. ECU
2. Engine Stop Switch
3. Ignition Switch
4. Joint Connector F
5. Fuse Box 1
6. Ignition Fuse 15 A
7. Relay Box
8. Fuel Pump Relay
9. Fuel Pump
10. Frame Ground 1
11. Frame Ground 3
12. Starter Relay
13. ECU Fuse 15 A
14. Main Fuse 30 A
15. Battery
16. Engine Ground
Stick Coil #1: Service Code 51
Stick Coil #2: Service Code 52
Stick Coil #3: Service Code 53
Stick Coil #4: Service Code 54
Fuel Pump Relay Removal/InstallationSubthrottle Sensor Output Voltage Inspection
Measure the output voltage at the subthrottle sensor in
the same way as input voltage inspection, note the following.
Disconnect the subthrottle sensor connector and connect
the setting adapter [A] between these connectors.
Special Tool - Throttle Sensor Setting Adapter: 57001
-1538
...
Cam Wear Inspection
Remove the camshafts (see Camshaft Removal).
Measure the height [A] of each cam with a micrometer.
If the cams are worn down past the service limit, replace
the camshaft.
Cam Height
Standard:
Exhaust 35.043 35.157 mm
(1.3796 1.3841 in.)
Intake 38.243 38.357 mm
(1.5056 1.5101 in. ...
Water Pump Housing Assembly
NOTICE
Do not reuse the mechanical seal and oil seal.
Apply high-temperature grease to the new oil seal lips [A].
Press the new oil seal into the housing with a bearing
driver [B] until it stops at the bottom surface [C] of the
housing.
Special Tool - Bearing Driver Set: 57001-1129
...