After replacing the engine oil, it is recommended to 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 by the computer is not initialized, the wrench indicator light may not turn off or it may turn on earlier than normal.
Refer to Maintenance Monitor.
Mazda 6 Owners Manual: Locking, Unlocking the Doors
NOTE
The system may not operate if you are too close to the windows or door
handles.
If the key is left in the following areas and you leave the vehicle,
the doors may be locked depending on the radio wave conditions even if the key
is left in the vehicle.
Around the dashboard
...
Mazda 6 Owners Manual: No.6 windshield fogged
When performing an asterisked (*) troubleshooting inspection, shake the
wiring harness and connectors while doing the inspection to discover whether
poor contact points are the cause of any intermittent malfunctions. If there
is a problem, check to make sure connectors, terminals and wir ...