MAZDA6. KEY BUZZER.
If you do not like the confirmation sound of pressing a key (buzzer) on the console panel or steering wheel, then you can turn it off:
1. turn off the radio
2. press and hold the "seek" button down
3. press and hold the "5" button until a confirmation signal
Note: this cheat does not work on cars with a Bose sound system!

What are hidden button combinations?
On your stereo, bose and non-bose, you can, by pressing different combinations of two buttons, turn various features on or off, or test certain aspects of your stereo system.

Why would you bother with some hidden features?
Aren't you tired of the fact that every time you press the button, it beeps? It infuriates me that when I switch between stations or tunes on a CD to find a good song, I always hear this - "beep beep beep beep beep beep beep beep beep beep".

Is this a complete list of hidden features?
No, and you can be sure that someday someone bored in their Mac for a couple of hours and pushing buttons will find them. (or steal the engineer and torture him until he tells us all the secrets)

Do these features work for both bose and non-bose systems?
Yes and no. You can check the hidden key combinations on both systems and you can see the message on the display, which will suggest that it works for you, but there are certain functions that will work as it is shown on the display, "only" on a certain system (see combinations below, if it works on both systems then I'll mark it as "both")

What can you do to help?
Well, if you're as bored as I am today, then go get in your car and start pushing some buttons. If you find some combination or feature that is not listed here, post it here anyway.

How to exit the function change mode.
Some feature messages do not disappear from the screen. If so, just press the stereo power off button, and then turn the power back on, but remember which options you changed, because the option will remain changed until you change it with the same button combination.

Display test:
Turn on stereo - Hold Power button + Seek Up button
Both: Diagnosis of backlighting all icons on the display to check for non-functional or dim areas

Checking audio channels:
Turn on stereo - Hold Power button + Auto M Down button
Both: Diagnostics of the health of the audio channels in order to determine the status of the speakers and the pairing between the head unit and each speaker.
1. Left door speaker and tweeter
2. Right door speaker and tweeter
3. Right rear door speaker and subwoofer
4. Left rear door speaker and subwoofer

Reset stereo settings:
Turn stereo on - Hold down Tune/Settings + (any other button except stereo power button)
Both: This will reset everything sound settings bass/treble/mid/fade... to factory settings. (but will not reset station memory)

Checking the strength of the radio signal:
Turn on the stereo - Hold the power button + "2" button
Both: The combination allows you to display the signal strength of the radio wave or the status of the antenna, or the radio and antenna mount
(displays S-METER and numbers from 0 (worst) to 9 (best))

Antenna off/on:
Turn on the stereo - Hold the power button + "AM" button
Non-BOSE: no effect
BOSE: ???
(I think this is just a status display. When the system is playing a CD - off, when the radio is on. Any other information is welcome)

Amplifier off/on:
Turn on the stereo - Hold the power button + "Scan Up" button
Both: Diagnostics of the health of the amplifier's audio output channel to determine the status of the amplifier and pairing between the head unit and the amplifier.

Button test:
Turn on stereo - Hold power button + "MD/Tape" button
Both: This option verifies that all system buttons are in working order. All buttons will beep when pressed, even the buttons on the steering wheel.

Self Diagnosis - (lost wiring still need to check this function again):
Turn on stereo - Hold power button + AM button + "MD/Tape" button
Both: Walkthrough correct operation audio systems. The first message displayed is who made your head unit and number. To stop diagnostics, turn the ignition key to the LOCK position

If someone has cheats for Mazda - write to me.
I will definitely post them on this page with a link to the sender!