Test every fuse out of its holder

With the game off, pull each fuse and check it on the continuity range rather than trusting its looks; this also shows up cracked fuses and bad holders. Many under-playfield fuses lack labels, so use the manual and fit exactly the rating and type it gives (slow-blow or normal), never larger.

Systems

• Gottlieb System 1

Related tips

• Testing a fuse
• Checking a fuse properly
• Where the fuses are
• Fuse rating rules
• Fuse letter codes

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