Depress the button on the seat belt buckle. If the belt does not fully retract, pull it out and check for kinks or twists. Then make sure it remains untwisted as it retracts.

NOTE
If a belt does not fully retract, inspect it for kinks and twists. If it is still not retracting properly, have it inspected at an Authorized Mazda Dealer.
Fastening the Seat Belt
Front Shoulder Belt AdjusterMazda 6 Owners Manual: Service warnings
Component Disassembly
Disassembling and reassembling the components of the air bag system
can render the system inoperative, which may result in serious injury or
death in the event of an accident. Do not disassemble any air bag system
components.
Wiring Harness Repair
Incorrec ...
Mazda 6 Owners Manual: Registering Your Vehicle in A Foreign Country (Except United States and Canada)
Registering your vehicle in a foreign country may be problematic depending on
whether it meets the specific emission and safety standards of the country in which
the vehicle will be driven. Consequently, your vehicle may require modifications
at personal expense in order to meet the regulation ...