Here's a weird one. We have a 2008 smart with about 18,000 miles. My wife had driven it about 20 miles to a meeting the other day and locked it. After about an hour she came out to open the car. It opened fine, but when she shut the door it didn't latch. Nothing in the way. No obvious reason (seat belt caught). I arrived to help and tried unlocking and locking with both the key as well as the manual system inside the car. Nothing worked. Eventually, I sent her home in the other car and drove the smart myself with my arm outside the open window to hold the door shut on the highway. At the normal self locking speed I heard a click, but the wrong door. I could still push my door open. At higher highway speeds I pressed the "lock" button on the dash again. I didn't try pushing the door at that point on the highway, but when I arrived back home, the door had locked. It has locked and unlocked perfectly since then. Anyone else experienced this? If not, try my method in an emergency if it does.
Ron Gaus, St. Louis