Alrighty..
Firstly a systematic approach needs to be done to eliminate a couple of things. Unplug power (from the wall) and remove.
Remove all 6 balls (before or after) and lift playfield to its upright position.
As Blair and Andrew have suggested, a check of the switch in shed would be my first area to look at. If no issues identified then....
There is a note in Clay's guide about the loom rubbing against the upper right flipper coil stop. I would carefully inspect this area to ensure the loom isn't shorting.
I would also do a visual inspection of the diodes on the coils to ensure none have broken.
See how you go. We'll get it sorted.
