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 AdjusterBlower Motor Removal [Full Auto Air Conditioner]
NOTE:
The blower motor is located on the A/C unit as shown in the figure.
Perform the work from the front passenger side in the posture shown in the
figure.
1. Set the air intake mode to FRESH.
2. Disconnect the negative battery cable.
3. Remove the following ...
Stop Vehicle in Safe Place Immediately
If any of the following warning lights turns on, the system may have a
malfunction. Stop the
vehicle in a safe place immediately and contact an Authorized Mazda Dealer.
...
Input/Turbine Speed Sensor Removal/Installation [FS5 A EL]
CAUTION:
Always use a new bolt. If the removed input/turbine speed sensor installation
bolt is reused, it may cause oil leakage.
A sealant coating is applied to the input/turbine speed sensor installation
bolt to prevent oil leakage from the installation bolt hole which passes ...