Gottlieb Freddy A Nightmare on Elm Street (Gottlieb, 1994) System 3 REPAIR HELP NEEDED.....

[Chicoman]

Hey everyone I'm new to the forums but not new to pinball repair.

However I am at my wits end with a Gottlieb System 3 Control Board issue. Can't get the pinball to boot up. When I test the control board out of circuit running power off a battery the LED lights and flashes normal but then pauses briefly and continues to flash pausing briefly every few seconds. I thought that indicated a problem with the battery but a new battery didn't do the trick. Neither did replacing the U6 chip which has been known to go bad on these boards.

I've done the Randy Fromm IC test on the IC Chips and no problems there or so it seems. I did replace a bad U7 chip but everything else checks normal.

Also replaced the one Electrolytic cap that showed bad too.

I have no way of testing the ceramic capacitors without an insulation tester.....I've never had one go bad in another pinball machine though.

Any thoughts or suggestions that might help?

I've tested the voltage from the transformer to the P1 plug for the control board and it all tests good.

I don't have another System 3 Control Board to test it.

Just looking for some suggestions?

I did replace the U11 chip also and no luck there either.

Any help is appreciated.

Cheers