The official notice
Defect
On certain vehicles, a hydraulic sensor in the transmission could malfunction. If this happens, the transmission may slip and cause vibrations or abnormal noises while driving. This can also cause a malfunction indicator lamp to turn on. If you continue driving, this could result in a loss of power to the wheels.
Safety Risk
A loss of power to the wheels could increase the risk of a crash.
Remedy
Subaru will notify owners by mail and instruct you to take your vehicle to a dealer to update the Transmission Control Unit (TCU) software. The vehicle will be inspected after a drive test, and if certain trouble codes (DTCs) are stored, the hydraulic sensor harness will also be replaced. If vehicles are confirmed to have experienced, or are currently experiencing low drive chain tension, the transmission assembly will be replaced.