Yamaha WR450F 2021 Owner's Service Manual page 298

CHECKING THE IGNITION COIL ............................................................8-65
CHECKING THE CRANKSHAFT POSITION SENSOR ...........................8-66
CHECKING THE LEAN ANGLE SENSOR ...............................................8-67
CHECKING THE STARTER MOTOR OPERATION ................................8-67
CHECKING THE STATOR COIL..............................................................8-67
CHECKING THE RECTIFIER/REGULATOR ...........................................8-67
CHECKING THE SPEED SENSOR .........................................................8-68
CHECKING THE FUEL SENDER ............................................................8-68
CHECKING THE RESISTOR ...................................................................8-68
CHECKING THE RADIATOR FAN MOTOR.............................................8-69
CHECKING THE COOLANT TEMPERATURE SENSOR ........................8-69
CHECKING THE THROTTLE POSITION SENSOR INPUT VOLTAGE...8-70
CHECKING THE INTAKE AIR TEMPERATURE SENSOR .....................8-70
CHECKING THE GEAR POSITION SWITCH ..........................................8-71
CHECKING THE INJECTOR....................................................................8-71