Move the signal lever down (for a left turn) or up (for a right turn) to the stop position. The signal will self-cancel after the turn is completed.
If the indicator light continues to flash after a turn, manually return the lever to its original position.

The turn signal indicators in the instrument cluster flash according to the operation of the turn signal lever to show which signal is working.

NOTE
Turn and Lane-Change Signals
Lane-Change Signals and Three-Flash Turn SignalMazda 6 Owners Manual: No.4 air intake mode does not change
When performing an asterisked (*) troubleshooting inspection, shake the
wiring harness and connectors while performing the inspection to discover
whether poor contact points are the cause of any intermittent malfunctions.
If there is a problem, check to make sure connectors, terminal ...
Mazda 6 Owners Manual: Power window motor inspection
Drivers Side
1. Disconnect the power window motor connector.
2. Apply battery positive voltage to the power window motor terminals E and F
and inspect the operation the power window motor operation.
If not as specified, replace the power window motor.
3. Apply battery positive voltage ...