Use the solenoid test to check the sound lines
On System 3-6, step manually through solenoids 9 to 13 in the solenoid test; each should give a different sound. If not, check driver transistors Q31, Q33, Q35, Q37 and Q39. System 7 has its own sound test (test 00) right after the display test, and its sounds come from a CPU board PIA instead.
Systems
Related tips
- How System 3-6 games trigger sounds
- Sound test fine but many game sounds missing: a sound line stuck on
- Quick sound checks by grounding
- Wrong sounds play
- Background sound never stops at game over: sound-line driver chip
- Missing words or sounds from cracked connector pins
- Garbled sound at game start and no background sound: driver board header joints
- Extra sound lines on World Cup and Disco Fever
Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part Three, Clay Harrell (pinrepair.com)