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.
Mazda 6 Owners Manual: Exhaust system
EXHAUST SYSTEM INSPECTION
Start the engine and inspect each exhaust system component for exhaust gas
leakage.
If leakage is found, repair or replace as necessary.
EXHAUST SYSTEM REMOVAL/INSTALLATION
Warning
When the engine and exhaust system are hot, they can badly burn.
Turn off t ...
Mazda 6 Owners Manual: Ignition switch inspection
1. Disconnect the negative battery cable.
2. Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION)
3. Disconnect the ignition switch connectors.
4. Inspect for continuity between the ignition switch terminals using an
ohmmeter.
If not as specified, replace the ignition switch.
...