At these temperatures, the brakes may not release after being applied, even when the driver's foot is no longer on the brake pedal. This can occur withour prior warning, possibly resulting in a crash.
Service Brakes, Hydraulic — Foundation Components — Master Cylinder
On certain passenger vehicles, the brake master cylinders may not function properly in ambient temperatures below freezing 32 degrees Fahrenheit and lower).
Dealers will replace the master cylinders. Owner notification began March 21, 2002. Owners who take their vehicles to an authorized dealer on an agreed upon service date and do not receive the free remedy within a reasonable time should contact Subaru at 1-800-782-2783.