Williams 'LOCK' relay is burned looking in every game. This is because this
is a continuous duty solenoid (It's on all the time) and as such gets hot
and the wrapper gets burned. This is normal and rarely affects operation of
the game. Usually you can force the relay contacts closed and avoid
replacing the coil if it is bad. The purpose of the coil is to force the
game into 'game over' mode upon switching power on if power is turned off in
the middle of a game. If you can live with this then you don't need to
worry about replacing the coil should it ever go bad.