Subaru Legacy BN/BS (2015-2019) Owners Manual: Replacing battery of transmitter

1. Open the key head using a flat-head screwdriver.

2. Remove the transmitter case from the key head.

3. Open the transmitter case by releasing the hooks.

1) Negative (−) side facing up

4.  Replace the old battery with a new battery (Type CR1620 or equivalent) making sure to install the new battery with the negative (−) side facing up.
5.  Put together the transmitter case by fitting the hooks on the case.
6.  Reinstall the transmitter case in the key head.
7.  Refit the removed half of the key head.

After the battery is replaced, the transmitter must be synchronized with the remote keyless entry system's control unit. Press either the " " or " " button six times to synchronize the unit.