Look over every switch before first power-up

Spend ten minutes looking at every relay, score motor and playfield switch before switching on. Broken blades, obviously bent switches and wires broken off solder lugs are easy to see, and finding them now saves tracing the schematic later.

Systems

• Electro-mechanical

Related tips

• Self-cleaning "over-wipe" switch adjustment
• Why EM switch contacts get dirty
• File EM switch contacts
• Switch gap and adjustment targets
• Tighten a switch stack before adjusting it
• Adjust a leaf switch at the stack
• Normally open, normally closed and make/break switches
• Game stopped working after filing switches

Source: Repairing Electro-Mechanical (EM) Coin Operated Games to 1978, Part One, Clay Harrell (pinrepair.com)