Probably a shorted transistor that controls the lamp.

check the diode on that socket perhaps.

wait,

you sure it just started happening>? I used to own a cyclone and recall one of those lights being on all the time. It's settable in adjustments I think.

Pretty sure it's supposed to be on. (wait, not pretty sure... but look into it)

No, that would affect all lamps in a row or column

Check your bonus multiplier memory setting in the adjustments. Item #52. If this is set you "yes" it will remember the lighted multiplier settings from ball to ball and the last play. Make sure this is set to "no" - the lighted lamps are then not stored and reset at each ball start.

In the set up menus, you can set one of the bonus lights to be on (blinking). When you reach that bonus level by shooting boomerang shots, it lights extra ball.

So, is the light on steady or blinking? Is it the only bonus light that is on? One blinking light = everything probably OK, more than one light or one light on steady = a problem.

Don C.