Take the appropriate action and verify that the warning light turns off.

Taking Action
Message Indicated on DisplayMazda 6 Owners Manual: Coil removal/installation
Note
Do not remove the coil unless you are replacing it.
When only the coil is replaced, the immobilizer system reprogram
procedure is not necessary.
1. Disconnect the negative battery cable.
2. Remove the column cover.
3. Remove in the order indicated in the table.
4. Install in ...
Mazda 6 Owners Manual: Battery recharging
Warning
Keep any flammable away from the battery, otherwise evaporated gas
of the battery fluid may catch fire, and cause serious injury or death.
Caution
When removing the battery, disconnect the negative battery cable
first and install it last to prevent damage to electrical compo ...