This corrosion can possibly create open connections in circuits which control the restraint deployment, possibly causing inadvertent air bag deployment.
Air Bags — Frontal — Sensor/Control Module-Inactive
Vehicle description: Passenger vehicles. Moisture can enter the air bag inflatable restraint electronic control module (ECM) and cause corrosion on portions of the ECM printer circuit boards.
Dealers will inspect the exterior of the ECM. If there is no indication of moisture, a cover will be installed over the ECM. If there is indication of moisture, the dealer will replace the ECM and install a cover over the new ECM.