Invacare Comet Operating Manual page 32

Activating or deactivating an acoustic signal
Please proceed as follows to activate or deactivate an acoustic signal for a particular function:
1) Switch off the electronic system.
2) Enter the keystroke combination and hold.
3) Switch on the electronic system
4) Wait two seconds until the appropriate blink code is displayed on the battery charge display,
then release the keys. Do not hold the keystroke combination down for more than five seconds.
5) If LED D7 blinks five times subsequently the acoustic signal has been successfully activated.
6) The electronic system will return to normal operating status automatically.
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