The official notice
Defect
On certain vehicles, long-term exposure to high absolute humidity and temperature, combined with high temperature cycling, may eventually degrade the propellant contained in the passenger-front airbag. This could cause the airbag to deploy with more force than normal. If the airbag inflator ruptures, fragments could be propelled toward vehicle occupants or cause damage to the airbag assembly, preventing its proper function.
Safety Risk
If the vehicle is involved in a crash requiring an airbag deployment, the airbag inflator could rupture and create a risk of injury.
Remedy
General Motors will notify owners by mail and instruct you to take your vehicle to a dealer to replace the passenger-front airbag. Note: The Canadian climate results in the propellant degrading slowly. This recall is being conducted as a precaution to address future risk. It is expected that all airbag inflators will be replaced before their function would be affected.