Press the CLEAR and - keys on the numeric keypad together to enter test mode.
TEST MODE: KEYS
KEY UP MINUS
Press any key, KEY DOWN xxx and then KEY UP xxx will appear.
To test encoders press the UP key on the transport panel
TEST MODE: ENCODERS
TURN ANY ENCODER
All encoders can now be tested.
To exit test mode, press the CLEAR and - keys on the numeric keypad together.
Normally if test mode is accessible, then the panel is fully operational.
More detailed notes on panel test software.