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 AdjusterInput/Turbine Speed Sensor Inspection [FS5 A EL]
CAUTION:
Water or foreign objects entering the connector can cause a poor connection
or corrosion. Be sure not to drop water or foreign objects on the connector
when disconnecting it.
On-Vehicle Inspection
1. Perform the following procedures.
a. Remove the battery cover..
b. ...
Starter Removal/Installation [Mzr 2.0, Mzr 2.5]
WARNING:
Remove and install all parts when the engine is cold, otherwise they can
cause severe burns or serious injury.
When the battery cables are connected, touching the vehicle body with starter
terminal B will generate sparks. This can cause personal injury, fire, and d ...
Before Service Precaution [Mzr 2.0, Mzr 2.5]
WARNING:
Fuel vapor is hazardous. It can very easily ignite, causing serious injury
and damage. Always keep sparks and flames away from fuel.
Fuel line spills and leakage from the pressurized fuel system are dangerous.
Fuel can ignite and cause serious injury or death and damag ...