Yamaha WR250F Owner's Service Manual page 334

ELECTRICAL COMPONENTS.......................................................................9-60
CHECKING THE SWITCHES ..................................................................9-64
CHECKING THE BULBS AND BULB SOCKETS ....................................9-67
CHECKING THE FUSES .........................................................................9-68
CHECKING AND CHARGING THE BATTERY........................................9-69
CHECKING THE RELAYS .......................................................................9-72
CHECKING THE DIODE ..........................................................................9-73
CHECKING THE IGNITION SPARK GAP................................................9-73
CHECKING THE SPARK PLUG CAP ......................................................9-73
CHECKING THE IGNITION COIL ............................................................9-74
CHECKING THE CRANKSHAFT POSITION SENSOR...........................9-74
CHECKING THE LEAN ANGLE SENSOR...............................................9-75
CHECKING THE STARTER MOTOR OPERATION ................................9-75
CHECKING THE STATOR COIL .............................................................9-76
CHECKING THE RECTIFIER/REGULATOR ...........................................9-76
CHECKING THE SPEED SENSOR .........................................................9-77
CHECKING THE FUEL SENDER ............................................................9-77
CHECKING THE RESISTER ...................................................................9-77
CHECKING THE RADIATOR FAN MOTOR ............................................9-78
CHECKING THE COOLANT TEMPERATURE SENSOR........................9-78
CHECKING THE THROTTLE POSITION SENSOR ................................9-79
CHECKING THE THROTTLE POSITION SENSOR INPUT VOLTAGE ..9-79
CHECKING THE INTAKE AIR PRESSURE SENSOR ............................9-80
CHECKING THE INTAKE AIR TEMPERATURE SENSOR .....................9-80
CHECKING THE FUEL INJECTOR .........................................................9-81