Tesla S Owner's Manual page 69

Brakes
When you use the touchscreen to
manually apply the parking brake,
the red parking brake indicator lights
up on the instrument panel .
If the parking brake experiences an
electrical issue, the amber parking
brake indicator lights up and a fault
message displays at the top of the
instrument panel.
Caution: In the unlikely event that Model S
loses electrical power, you cannot access
the touchscreen and are therefore unable
to release the parking brake. Contact
Tesla.
68 Model S Owner's Manual