Yamaha WR250F 2021 - Page 351

FUEL INJECTION SYSTEM
8-50
Fault code No. 50
TIP
Before troubleshooting, disconnect the starter motor lead from the starter relay.
Fault code No. 70
TIP
It is not a malfunction.
If the engine is forcibly stopped by leaving idle, the recovered state is recorded by malfunction mode.
6 Delete the fault code. Confirm that the fault code has
a condition of “Recovered”
using the Yamaha diagnostic
tool, and then delete the fault
code.
Fault code No. 50
Item ECU: faulty ECU memory.
Fail-safe system
Unable to start engine
Unable to drive vehicle
Diagnostic code No. —
Diagnostic tool display —
Procedure —
Item
Probable cause of malfunc-
tion and check
Maintenance job
Confirmation of service com-
pletion
1 Faulty ECU. Replace the ECU. Push the start switch (main
relay ON), and then check the
condition of the fault code using
the malfunction mode of the
Yamaha diagnostic tool.
Check that the fault code num-
ber is not displayed.
Fault code No. 70
Item
Engine forcibly stops when the vehicle is left idling for a long period
of time.
Fail-safe system
—
Unable to drive vehicle
Diagnostic code No. —
Diagnostic tool display —
Procedure —
Item
Probable cause of malfunc-
tion and check
Maintenance job
Confirmation of service com-
pletion
Fault code No. 46
Item
Vehicle system power supply: normal voltage is not supplied to the
ECU.