for my d&d the problem of fuse1 was a bad opto,check this.

change your old battery...if it leak acid...change your battery of place with wire.did you have a problem with your opto during play?

ok,first what happen when you start a game?i show you on this picture for better place for battery,and change these connector for molex ,i fix some problem with this,now its perfect.check your opto with a digital camera.f1 fuse is a bad opto.d&d 004.JPGd&d 001.JPG

mine do that before i fix my opto.i change a lens,i resolder my opto board.you can fix yours or find a new from http://www.greatlakesmodular.com/ but (out of stock).

your wire soldered is not suppose to be there!! sw9 is a transistor,look at my picture on my mpu you can see that.for your opto start your machine a take a picture of the lens with a digital camera in the night.http://www.flippers.be/balltrough_problems.html

i know is stupid question,but did you check all fuses?like under playfield.

where is this relay?

did you check a connector,wires of contact flipper buttons?