Because the antenna system is equipped with a capacitor, the continuity cannot be checked. Therefore proceed the following simple inspection.
Turn the AM radio on.
Tune to the frequency that there is no broadcast and you will hear a buzzing sound.
Turn a work light on and shake it around the antenna rod. (around 10—20 mm {0.40—0.78 in})
CAUTION:
Use a fluorescent light type for the inspection. Accurate diagnostic cannot be done with a different type of light.

If a whirring sound from the speaker synchronized to the work light movement is confirmed, the antenna system is normal.
Coil Antenna Removal/Installation
Entertainment Personalization Features Setting ProcedureStop Vehicle in Safe Place Immediately
If any of the following warning lights turns on, the system may have a
malfunction. Stop the
vehicle in a safe place immediately and contact an Authorized Mazda Dealer.
...
Accessory Sockets
Only use genuine Mazdaaccessories or the
equivalent requiring no greater than 120 W
(DC 12 V, 10 A).
Type A
The accessory sockets can be used
regardless of whether the ignition is on or
off.
Type B *
The ignition must be switched to ACC or
ON.
With CD Player
Without CD Player
...
Air Filter Inspection [Mzr 2.3 Disi Turbo]
Airflow Inspection
1. Remove the air filter..
2. Blow from port A and verify that there is airflow from port B.
If there is no airflow, replace the air filter..
3. Blow from port B and verify that there is airflow from port A.
If there is no airflow, replace the air filt ...