On vehicles equipped with an engine block heater, the heater power cord may become damaged in cold temperatures, resulting in risk of electrical shock and personal injury.
The power window and lock switches may stop working, and the module that controls these functions can overheat. This may cause a fire hazard.
The weight on the key ring, combined with a jarring event may cause the ignition switch to move out of the run position, turning off the engine.
The driver's front air bag may short internally, preventing deployment when needed in an accident.