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 ProcedureAccessory 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
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Camshaft Position (CMP) Sensor Removal/Installation [Mzr 2.0, Mzr 2.5]
CAUTION:
When replacing the CMP sensor, make sure there is no foreign material on
it such as metal shavings. If it is installed with foreign material, the sensor
output signal will malfunction resulting from fluctuation in magnetic flux and
cause a deterioration in engine control.
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Head Restraints
Your vehicle is equipped with head
restraints on all outboard seats and the
rear center seat * . The head restraints
are intended to help protect you and the
passengers from neck injury.
WARNING
Always drive with the head restraints
installed when seats are being used and
make s ...