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 ProcedureReplacing Exterior Light Bulbs
Headlights (With xenon fusion
headlights)
Low/High beam bulbs
You cannot replace the low/high beam
bulbs by yourself. The bulbs must be
replaced at an Authorized Mazda Dealer.
Headlights (With halogen headlights)
Low-beam bulbs
If you are changing the right bulb, start
the engine, turn ...
Oil Control Valve (OCV) Removal/Installation [Mzr 2.3 Disi Turbo]
1. Remove the battery cover..
2. Disconnect the negative battery cable..
3. Remove the charge air cooler..
4. Remove the ignition coils..
5. Disconnect the ventilation hose from the cylinder head cover..
6. Remove the cylinder head cover..
7. Remove in the order indicated in the table.
...
Oil Seal (Differential) Replacement [C66 M R]
1. Remove the aerodynamic under cover No.2 and the splash shield as a single
unit..
2. Drain the manual transaxle oil..
3. Disconnect the drive shaft (LH) from the MTX..
4. Disconnect the drive shaft (RH) from the joint shaft..
5. Remove the joint shaft..
6. Remove the oil seal (LH).
...