Yamaha YFM660R Owner's Manual page 78

ACB-09E
Coolant temperature warning
light does not come on.
Push the start switch with the
transmission in the neutral position.
Coolant temperature
warning light comes on
momentarily.
Coolant temperature and
electrical circuit are OK. Go
ahead with riding.
Coolant temperature warning light checking method
Turn the main switch to "ON" and
the engine stop switch to "
Coolant temperature
warning light does not
come on.
".
Ask a Yamaha dealer to
inspect the electrical circuit.
4-7
Coolant temperature
warning light comes on.
EBU00714