Audio unit button does not work (without navigation)

NOTE:

Check the vehicle battery condition first (see 12 VOLT BATTERY TEST ).
Check the connectors for poor connections or loose terminals.
If the audio unit does not turn on, go to AUDIO UNIT POWER SWITCH WILL NOT TURN ON .

Turn the ignition switch to ON (II).
Using the owner's manual, check the operation of the faulty button.
Is the symptom still present?

YES -
- Except DX model: Substitute a known-good center panel (see EXCEPT DX MODEL ), and recheck. If the symptom/indication goes away, replace the original center panel (see EXCEPT DX MODEL ). If the symptom is still present, substitute a known-good audio unit (see AUDIO UNIT REMOVAL/INSTALLATION ), and recheck. If the symptom/indication goes away, replace the original audio unit (see AUDIO UNIT REMOVAL/INSTALLATION ).
- DX model: Substitute a known-good audio unit (see DX MODEL ), and recheck. If the symptom/indication goes away, replace the original audio unit (see DX MODEL ).
NO -The system is OK. There is a chance the button was incorrectly used.