I have a Special Force and just recently the playfield "special" light in the left outlane and the "extra ball" light for the middle ramp went out. Both had brand new LED's placed in them just under 2 years ago. They did not go out at the same time if I remember correctly (although I could be wrong). I had asked about GI lights going out on 6803's a while back and it was suggested that I replace the sockets because the weld points fail. With both of these failed playfield lights I have replaced the socket diodes with known working ones and connected the bulbs (tried incandescent and LED's) directly to the strap and supply wire directly (through known good diodes) to entirely bypass the socket to make sure it is not a problem upstream. The lights still do not work. My obvious question here is what could the problem be? I know Williams machines from this era have row and column matrices that cause an entire group of lights to go out if a transistor goes bad, but I am very unfamiliar with Bally/6803 circuit design.
I also have a similar problem on my Escape From the Lost World pin (also 6803). One of the playfield score lights and one of the two "escape" lights is out for no apparent reason. I attributed this to a socket that suddenly went bad. I have not had time to test these (other than with known-working LED's).
Any help is appreciated. Thanks!