Chevrolet 2003 Venture Owner's Manual page 247

Adjusting the Speakers (Balance/Fade)
AUDIO: To adjust the balance between the right
and the left speakers, press and release the AUDIO
button until BAL appears on the display. Then press and
hold the up or the down arrow to move the sound
toward the right or the left speakers.
To adjust the fade between the front and the rear
speakers, press and release the AUDIO button until
FAD appears on the display. Then press and hold the up
or the down arrow to move the sound toward the front
or the rear speakers.
To adjust balance or fade to the middle position, select
BAL or FAD. Then press and hold AUDIO for more
than two seconds until you hear a beep. L and a zero
or F and a zero will appear on the display.
To adjust both tone controls and both speaker controls
to the middle position, first end out of audio mode
either by pressing another button, causing the radio to
perform that function, or by waiting five seconds for
the display to return to time of day. Then press and hold
AUDIO for more than two seconds until you hear a
beep. CEN will appear on the display.
Radio Messages
CAL (Calibration): Your audio system has been
calibrated for your vehicle from the factory. If CAL
appears on the display it means that your radio has not
been configured properly for your vehicle and must
be returned to the dealership for service.
LOC (Locked): This message is displayed when the
THEFTLOCK@ system has locked up. You must
return to the dealership for service.
3-64