Troubleshooting - Yamaha YZ450FP 2023 Owner's Service Manual

EAM30288

TROUBLESHOOTING

The fuel pump fails to operate.
TIP
Before troubleshooting, remove the following part(s):
1. Seat
2. Side cover (left/right)
3. Shroud (left/right)
4. Fuel tank
5. Air filter case cover
1. Check the fuel pump system wire
harness connections.
OK
2. Check the fuse.
Refer to "CHECKING THE FUSES"
on page 8-47.
OK
3. Check the battery.
Refer to "CHECKING AND
CHARGING THE BATTERY" on
page 8-47.
OK
4. Check the engine stop switch.
Refer to "CHECKING THE
SWITCHES" on page 8-45.
OK
5. Check fuel pressure.
Refer to "CHECKING THE FUEL
PRESSURE" on page 7-8.
OK
6. Check the fuel pump system wire
harness connections.
Refer to "CIRCUIT DIAGRAM" on
page 8-41.
OK
Replace the ECU.
FUEL PUMP SYSTEM
Reconnect.
NG
Replace the fuse(s).
NG
• Clean the battery terminals.
• Recharge or replace the battery.
NG
Replace the handlebar switch (left).
NG
Replace the fuel pump.
NG
Repair or replace the wire harness.
NG
8-43