YES.
Page 24 & 25 of the P2 manual (rev 1.1) states:
The low battery capacity warning alerts users when the battery is close to depletion during flight. When it appears,
users should promptly fly back and land to avoid accidental damage. The PHANTOM 2 has two levels of low battery
capacity warning. The first appears when the battery has less than 30% power and the second appears when it has
less than 15% power.
(1) When battery power drops below 30% and LED indicator will blink red slowly.
(2) At lower than 15% the LED indicator will blink red rapidly,
the PHANTOM 2 will also begin to descend and
land automatically. After it has landed, keep the throttle stick at its lowest point or execute CSC.
(3) There is a hidden third low battery threshold in addition to the 1st and 2nd level warnings. This uses 10.65V
as its threshold. Both this voltage threshold and the 2nd Level Low Battery Warning will trigger auto-landing.
Altitude can be maintained if necessary by pushing up on the throttle stick.
Personally I have never 'tested' it.