Check the transistor that drives them. It sounds bad.

LTG : )

You're going to want to fix that. Locked on flashers get very hot!
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info

Chris knows what of he speaks.

Remove the bulbs until you do fix it so nothing important gets melted.

LTG : )

Transistor Q10 on the Aux. Driver PCB is likely shorted from the 2 wires shorting together.

This is the small rectangular PCB in the upper right corner of the backbox with a ribbon cable running to it - NOT the big driver board.

Q10 is a TIP102 transistor.

You will also want to test its predriver, Q3, a 2n4403 transistor. Often times, when a transistor fails and locks on, it stresses the predriver.

Do you know how to test transistors? Do you have a multimeter? Do you know how to use it? I don't mean to insult your intelligence if the answer is yes, but I need to ask to know how to help you best.

In the meantime, remove the 2 flasher bulbs that are locked on until you can repair the board. They will melt plastic, and potentially further damage the board if they are locked on.

To test if a tip 102 os shorted to ground, put the meter into continuity mode then touch then test continuity between the tip of the transistor and the ground pad on the board. There should not be zero resistance.

Mark's instructions work for a quick and dirty TIP102 test.

Another way... put your meter in diode test and remove the board from the game

TIP102: Put the black lead of the DMM on the metal tab of the transistor. Put the red lead of the DMM on each of the two outside legs of the transistor one at a time. A reading of .4 to .6 volts should be seen. Put the red lead on the center transistor leg (collector), and a zero reading should be seen. Any other value, and the transistor is bad and will need to be replaced.

2N4403: Put the black lead of the DMM on the center leg of the transistor (note this transistor doesn't have a metal tab). Put the red lead of the DMM on each of the two outside legs of the transistor one at a time. A reading of .4 to .6 volts should be seen. Any other value, and the transistor is bad and will need to be replaced.