If a message is displayed in the center display, take appropriate action (in a calm manner) according to the displayed message.

KEY Warning Light (Some models)
Stop Vehicle in Safe Place ImmediatelyMazda 6 Owners Manual: Seat Belt Precautions
Seat belts help to decrease the possibility of severe injury during accidents and sudden stops. Mazda recommends that the driver and all passengers always wear seat belts.
(U.S.A. and Canada)
All of the seat belt retractors are designed to keep the lap/shoulder belts out of the way when ...
Mazda 6 Owners Manual: Immobilizer system reprogram procedure
Note
When an error occurs during the reprogram procedures, except when
the PCM is replaced, repeat the procedure from Step 1. If you still cannot
reprogram, confirm how many keys can start the engine. Then, perform the key
replacement or addition reprogram procedure according to the val ...