The SC-901 audio system in my 1999 C70 has some button-combinations, which are not all documented in the user's manual.

I'm talking about the ones where you switch off the radio, press and hold a button and then switch the unit back on, giving you access to certain settings.

I know the following:

1 - toggle speed driven volume adjustment
2 - custom equalizer
5 - locality setting

I tried the same with 3, but it gave some weird beep and the whole display came up (all icons).

Does anybody know what happens when you use 3, 4 and 6? I don't want to reset (or lock) everything accidentally (I don't know the radio unlock code).

 

I've tried all button combinations and none of them locked the deck, so no worries.

4 will tell you the version of your software(which I wish said 2 on mine so it could read CDrs)

6 i dont remember right now.

If anyone figures out a way around the CDr issue please share I'm damn interested in that.