Mitsubishi Stereo Security Code ...
Did you accidently run the battery down in your Sport? Decide to change the car battery? Take it to a local garage and now your stereo is demanding you enter some mysterious 'code'? This probably doesn't happen as often anymore since Mitsubishi's 'theft proof' stereo system has been around for a while and most owners have long since gone through some tribulation that required re-enabling the stereo. However, every once in a while the question still pops up. Ha, ha. No pun intended.:)
This is problamatic, however, for people buying their first used Mitsubishi as the former owners seem to rarely transfer any of the original paperwork to the new owners. Typically, a small laminated card was supplied with the vehicle and/or it was noted in the paperwork somewhere with the owners manual. If you didn't get this then eventually you'll have a problem.
Don't fret. If you didn't get the code when you bought your Mitsubishi all is not lost. Somewhere on the top or bottom outside of the stereo case is the part number and serial number. If you take these to your local Mitsubishi dealership along with your VIN number and current proof of ownership (typically a current registration) they'll be able to look up the original re-enable code. Unfortunately, at least for the Montero and Montero Sport getting to these numbers requires removing the stereo from the dash. On the Montero Sport removal requires disassembling half the dash - a several hour long job. In my humble opinion, it's usually easier to have the dealership take care of this particular problem and it's cheaper than replacing the head unit especially if everything works and you happen to be one of the lucky ones with the factory Infinity sound system, CD changer and amplifier.
If you get any flack from the dealership along the lines of 'we can't give you the code but we'll be happy to charge you to type it in' - find a different dealership and/or take it up with Mitsubishi. Personally, I sugest both. I've never had this happen but at least one person I know has.