First, don't be driving while doing this procedure.

Turn the radio off then on again. Dont touch any button except the 'm' button - the button you use to tune the radio frequency manually. Press and hold the 'm' button for TEN seconds or until the display changes. It should show the serial number of the unit. Normally when you press 'm', the display will reflect that by replacing 'ST' (stereo tuning) with 'm'. When holding the 'm' button for this procedure, the display should not do this - you will continue to see 'ST' for the ten seconds.

Now if the display has changed, you are in a configuration mode on the radio. Press the '>' or '<' button to change modes. The mode you want will display as "GAL (1-6)". This mode allows you to adjust the speed-sensitive volume control. Use the radio preset buttons 1-6 to set the amount of volume change you want at speed. Setting 1 is the smallest change, 6 is the highest.

I use 1 with the windows closed, level 4 when it's a nice enough day to drive with the windows open which makes for a lot of ambient noise at speed. The car is so quiet with the windows closed that setting 1 is plenty. On my car the default setting from the factory was 3 and it bugged me.

Then turn the radio OFF to save the settings. Turn it back on and go for a drive to test it.

The other semi-useful test mode will tell you the signal strength of any give station from 0 to 15 (highest). Use the preset buttons to change stations in the mode. This capability is probably used in the automatic tuning funtion in the radio.

The E46 guys found that the in-dash CD unit is slightly different but the procedure is similar.

Matt G.