Yamaha 2004 YP400 Service Manual page 309

FUEL INJECTION SYSTEM
7. Verify the operation of the sensor or actua-
tor.
• Sensor operation
The data representing the operating condi-
tions of the sensor appears on the trip LCD.
• Actuator operation
Set the engine stop switch to "ON" to oper-
ate the actuator.
* If the engine stop switch is set to "ON", set it
to "OFF", and then set it to "ON" again.
8. Turn the main switch to "OFF" to cancel the
the diagnostic mode.
NOTE:
To perform a reliable diagnosis, make sure to
turn "OFF" the power supply before every
check and then start right from the beginning.
7 - 8
FI