CPU sound diagnostic switch SW1 results
Once the game boots to attract mode, press SW1 (upper switch on the left edge of the CPU board): you should hear two test sounds, proving the speech (CVSD) and DAC circuits. Error tones: one, U23 RAM; two, U21 ROM; three, U22 ROM; four, U21 ROM; five, U22 ROM. No sound means the sound circuit or audio path is not working.
Systems
Related tips
- Sound circuits on the 11A and 11B CPU boards
- Testing the CPU board sound section with Leon's sound EPROM
- How System 11 makes sound
- Which System 11 sound board each game uses
- Using a D-11581 sound board in other System 11 games
- The D-11581 sound board: chips and ROMs
- D-11297, D-11298 and D-12338 sound boards
- No sound after board work: 1J15 and 1J16 swapped (they aren't keyed)
Source: Repairing Williams System 11 Pinball 1986 to 1990, Part Two, Clay Harrell (pinrepair.com)