1. Disconnect the negative battery cable..
2. Remove the front bumper..
3. Remove the horn..
4. Apply battery positive voltage to horn terminal A, and connect the horn retaining bolt to ground as shown in the figure, and then verify that the horn sounds.

If the horn does not sound, replace the horn.
Horn
Horn Removal/InstallationStarter Interlock Switch Inspection [Skyactiv G 2.0]
CAUTION:
Do not reuse the starter interlock switch if it is removed from the vehicle
even once. Replace with a new starter interlock switch when installing.
1. Disconnect the negative battery cable..
2. Disconnect the starter interlock switch connector.
3. Verify that the contin ...
Engine Oil
NOTE
Changing the engine oil should be performed by an Authorized Mazda Dealer.
Refer to Introduction for owner's responsibility in protecting your investment.
Recommended Oil
U.S.A. and CANADA
0W-20 full synthetic recommended:
Mazda Genuine Oil is used in your Mazda vehicle and is t ...
Check Valve Removal/Installation
Except U.S.A. And CANADA
1. Remove the floor under cover..
2. Remove in the order indicated in the table.
1
Evaporative hose
2
Check valve
3. Install in the reverse order of removal. ...