When the wipers no longer clean well, the blades are probably worn or cracked. Replace them.
CAUTION
To prevent damage to the wiper arms and other components, do not try to sweep the wiper arm by hand.
NOTE
When raising both windshield wiper arms, raise the driver's side wiper arm first. When lowering the wiper arms, slowly lower the wiper arm from the passenger's side first while supporting it with your hand. Forcefully lowering the wiper arms could damage the wiper arm and blade, and may scratch or crack the windshield.
1. Raise the wiper arm.
2. Open the clip and slide the blade assembly in the direction of the arrow.

3. Tilt the blade assembly and remove it from the arm.

CAUTION
To prevent damage to the windshield let the wiper arm down easily, do not let it slap down on the windshield.
4. Pull down the blade rubber and slide it out of blade holder.

5. Remove the metal stiffeners from each blade rubber and install them in the new blade.

CAUTION
So do not use the driver's side metal stiffeners on the passenger's side, or vice versa.
6. Carefully insert the new blade rubber. Then install the blade assembly in the reverse order of removal.

Wiper Blades
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Caution
Performing the following procedures without first removing the ABS
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Mazda 6 Owners Manual: Rear drain hose installation
Caution
If the rear drain hose is pinched or bent anywhere, the water in the hose may
not discharge and enter the inside of the vehicle. During and after installation
of the trims and the headliner, always make sure there is no interference with
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