Subaru Legacy BN/BS (2015-2019) Owners Manual: Door locks

Key replacement

Your key number plate will be required if you ever need a replacement key made. Any new key must be registered for use with your vehicle's immobilizer system before it can be used. The maximum ...

Locking and unlocking from the outside

NOTE If you unlock the driver's door with a key (including a mechanical key) and open the door while the alarm system is armed, the alarm system is triggered and the vehicle's horn sounds. In thi ...

Other materials:

Replacing battery of transmitter
Open the key head using a flat-head screwdriver. Remove the transmitter case from the key head. Open the transmitter case by releasing the hooks. 1) Negative (−) side facing up  Replace the old battery with a new battery (Type CR1620 or equivalent) ...