Help! Very strange problem with 04 Tahoe

[qposner]

When I unlock my 04 Tahoe with the key fob, the reverse lights light up in addition to the appropriate mirror lights and parking lights. However, if I am backed into a space or anything is within the range of the reverse sensors, they scream until I turn on the ignition. Any idea why this may be happening? The local dealer has never heard of this before and it is starting to drive me nuts (happens every day).

Thanks!

Quinn