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: Dtc c1145, c1155, c1165, c1175
Caution
When attaching the tester lead to the DSC HU/CM connector the SST
(49 G066 004) must be used.
Diagnostic procedure
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Mazda 6 Owners Manual: Power brake unit removal/installation
1. Remove the master cylinder. (See MASTER CYLINDER REMOVAL/INSTALLATION.)
2. Remove the wiper arm. (See WINDSHIELD WIPER ARM AND BLADE
REMOVAL/INSTALLATION.)
3. Remove the cowl grille. (See COWL GRILLE REMOVAL/INSTALLATION.)
4. Remove the wiper motor. (See WINDSHIELD WIPER MOTOR REMOVAL/INSTAL ...