Check the wires on the coil that launches the balls to the shooter lane. And test that coil in coil test.
Do all the other coils work in coil test? If not, check fuses.

Do all the switches in the ball trough register?

If the game thinks a ball is missing it won't start.

One other thing you could check is you didn't accidentally bend closed the slam tilt switches under the playfield. Or on the coindoor