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: Automatic transaxle fluid (atf) replacement
Warning
When the transaxle and ATF are hot, they can badly burn you. Turn
off the engine and wait until they are cool before changing the ATF.
1. Remove the oil dipstick.
2. Remove the oil drain plug and washer.
3. Drain the ATF into a container.
4. Install a new washer and the drain ...
Mazda 6 Owners Manual: Abs (abs/tcs) hu/cm system inspection
System Inspection
Preparation
1. Verify that the battery is fully charged. With the ignition switch on,
verify that the ABS and BRAKE system warning lights goes out after 2.4
seconds.
2. If the lights stays on after 2.4 seconds, the ABS (ABS/TCS) HU/CM
detects a failure. Follow the troubles ...