Problem: Game Plays but no Sound
- Troubleshooting Steps taken before benched: Fuses Checked
- Ohm checked Volume Pot
- Ohm checked and voltage checked cables going to the amp PCB
- Checked 5v,12v rail on SSIO PCB
Troubleshooting on the bench: Did a Sound and channel test (Failed){Used O-Scope on output of 8910s)
- Using digital Probe: Found Pins 27-29 on both F6 and F7 had a binary number of 010 which set the 8910s to inactive during any test that was ran
- Starting checking all Address and Data Buss only on the Sound Cpu side to verify pulses through buffers.(ok)
- Checked IO signals to from B13(ok)
- Downloaded a Test Rom to run more thorough direct test on the SSIO
- During a Square wave test on F6(this test bypasses any of the watchdog circuitry on the board) The Sound was very Low and square wave output was minimal
- Started probing control circuit for wave output and panning.
- Found that the RC signal on D11 was Dead
- Replaced D11 and Sound now works as it should.