dicer

Do any of the computers lose some kinda info when that is done? And what are the steps involved? Doors unlocked thus security system off?

PureDrifter

iTrader: (10)

everything is reset back to factory defaults. seat memory, radio, emissions readiness, etc...
just make sure the alarm's disabled and doors unlocked before you do it i guess, though frankly it doesnt matter afaik.

RA40

iTrader: (6)

As PD mentions. I tend to disconnect the battery with the doors unlocked.

sha4000

iTrader: (1)

Good advice so far.

YoshiMan

Make sure the doors are unlocked when you re-connect it as well. I usually put on a pair of earmuffs before I do anyway, because having the alarm go off when you're poking your head under the hood is rather unpleasant.