Just picked up a decent condition Police Force that has needed a few small repairs. At this point, the only major problem is that there is zero music. The sound is working, but the music is entirely absent. It had been working intermittently at first, getting progressively worse, and now is completely gone.

I've checked and re-seated all connectors and ribbon cables (ensuring that ribbon cables are plugged in with the red stripe at pin 1).

The game goes into music diagnostic mode through the settings but no music plays as you cycle through the different tracks. The sound-effect for hitting the middle ramp does play when you switch to a new track (each time at a different pitch that seems to be music-track-specific as the pitch drops back to normal when you cycle around to the start of the tracks)

I went in and tried the sound button on the main board: CPU switch SW1 (it's next to the CPU test button. Are all system 11 boards upside down? both my SS and now the PF are!). It plays a low pitched tone, then a high pitched. And there's my question.

From old posts I've read it seems that one tone indicates the u23 Ram chip is malfunctioning and two tones points to the u21 ram chip. Is the first, low pitched tone a reference tone, or the first tone in the error code?

As a side-note: there was some corrosion from the on-board battery backup; the holder actually crumbled apart when I went to replace the batteries and has since been removed and replaced with an off-board battery holder. The board was relative clean underneath, fortunately, and cleaned up readily save for the insulation on SRC2. Nonetheless, there don't seem to be any ill-effects of that board component being nude.

If someone out there has a working Police Force and could reach into the backbox and hit that sound test button and report back on the result it would be greatly appreciated.

Update:

By chance, I happen to have a Space Station set up right next to the Police Force: another williams 11B! The Space Station happens to be running fine with music and voice and all, so I tried the sound diagnostic button on the main board and it played the voice clip "condition green" over and over again. Based on wild conjecture alone, I bet that the Police Force would play a sound clip as well if everything were hunky-dory. This also leads me to believe that the two tones it is playing are indeed an error message.

As it stands, I'm ordering a replacement set of sound roms following the hunch that the u21 rom is bad.