Do you have a meter?
Do you have a manual? Here is a link to the IPDB one, download the English Manual
First fix the obvious...
On BSD, page 3-16 General Illumination is 6.3vac and comes off the transformer then into the power driver J113/J115 and is protected by a Slow Blow fuse. Is that fuse correct and good?
If it is good, the look at J120/J121 those connector are infamous for burning up.
Page 3-35 is a pict of the Power Driver board,
Page 3-36 is the pinouts of J120 (GI to backbox) and J121 (GI to playfield)
If you have neither GI on the Playfield and Backbox AND the fuse is good, then you have a Power Driver problem that needs component repair
If you have neither GI on the Playfield and Backbox AND the fuse is bad, you have/had a short on either PF or Backbox. Try another fuse, if it blows, disconnect J120/J121 and try again. If that does not blow, put on connector back until you isolate where it blows.
If you have backbox OR playfield GI but not both, then you definitely are looking at a J120 or J121 problem.
Hope this gets you started.