At a glance
What can fail
The front air bag sensors contain brass bushings that may corrode and crack in high-salt environments, allowing water to enter the sensor and potentially affecting air bag performance in frontal crashes.
What the fix does
Dealers will replace the original sensors with corrosion-resistant versions for vehicles in high-salt states, or provide lifetime free replacement for sensors that fail in other states.
Summarized — see the official notice for exact wording, dates, and contacts.