A method of curing a coating composition and a method of forming a cured coating on an automobile component are provided. The coating composition comprises a radical polymerizable compound and an organoborane-amine complex having an organoborane initiator, an amine blocking agent, and water. The method of curing the coating composition comprises the steps of combining the organoborane-amine complex, the radical polymerizable compound, and water to form the coating composition. Carbon dioxide is introduced into the coating composition or into a composition including at least one of the organoborane-amine complex, the radical polymerizable compound, and water prior to forming the coating composition. Carbonic acid is formed in situ within the coating composition through reaction of the water and carbon dioxide. The organoborane-amine complex is decomplexed with the carbonic acid thereby separating the organoborane initiator and the amine blocking agent. The radical polymerizable compound is polymerized using the organoborane initiator in the presence of oxygen.