At work today I had a 2004 Chrysler Crossfire come in for repairs that had been purchased as a used car from our dealership. It came in with the rear hatch lock not working. I did some searching on Google and found that those are not power locks, they are vacuum actuated locks. After 45 minutes or so of trying to find the problem I finally found that the hard plastic yellow vacuum hose was broken. I have attached photos of where the break was. When I was trying to diagnose the issue I was locking and unlocking the vehicle, since it was so loud inside the shop I couldn't hear the vacuum leak because it was only present for a few seconds while it tried to unlock/lock the hatch. So, if someone here has a problem with their rear hatch lock on the Crossfire's, get some place quiet to listen for the vacuum leak. It actually sounded like the leak was coming from, what would be, the lower passenger corner, but vacuum leaks have a way of reverberating and sounding like they're some place entirely. If the rear door is locked and won't unlock, there is possibly a way to fix the vacuum leak from inside the rear of the vehicle so the hatch will unlock, you just have to remove the right rear trim piece (behind the right rear window). If any further information is needed I can be reached at this email address