1. Disconnect the negative battery cable..
2. Remove the front bumper..
3. Remove the horn..
4. Apply battery positive voltage and connect the ground as shown in the figure and verify the horn beeper sound operation.

If the beep sound cannot be verified, replace the horn.
Horn
Horn Removal/InstallationCooling System Service Warnings [Mzr 2.0, Mzr 2.5]
WARNING:
Never remove the cooling system cap or loosen the radiator drain plug while
the engine is running, or when the engine and radiator are hot. Scalding engine
coolant and steam may shoot out and cause serious injury. It may also damage
the engine and cooling system.
Tu ...
Engine Oil Replacement [Mzr 2.0, Mzr 2.5]
WARNING:
Hot engines and engine oil can cause severe burns. Turn off the engine and
wait until it and the engine oil have cooled.
A vehicle that is lifted but not securely supported on safety stands is dangerous.
It can slip or fall, causing death or serious injury. Never work ...
Vehicle Engine Control Unit Reset Procedure
NOTE
This procedure is intended for vehicles with the engine oil flexible
maintenance setting
selected.
After replacing the engine oil, have a repair shop such as an Authorized
Mazda Dealer
perform the initialization (engine oil data resetting) of the recorded value. If
the value
recorded ...