At power-on the displays come on instantly with zeros, or a moving 0O0O0O pattern, with no 5 second wait and no relay clicks; no game can start.

Displays light at once showing zeros

Cause: One of the two normally closed slam switches (inside the coin door by the lock, and on the ball-roll assembly at the left of the cabinet) is open, or CPU J6 has failed, often from battery corrosion.

Checks

• Check both slam switches are closed and adjusted.
• Check the J6 connector and wiring.

Fix

• Repair the switch or connector, or defeat the slam circuit on the CPU board.

Systems

• Gottlieb System 1

Related tips

• The slam switch must be closed for the game to run
• CPU board reset circuit check
• Gottlieb reset circuit update
• Dead CPU board: first checks
• Genie: 1000s digit glows on players 1 and 3
• Never plug displays with the power on
• Power supply bring-up, step 3: displays
• Wrong-looking digits or bad "1"s

Source: Gottlieb System 1 Pinball Repair from 1977 to 1980, Clay Harrell (pinrepair.com)