I got a 3 inch nail which caused a slow leak. the TPMS light let me know I had a slow leak. I had bough a tire repair kit (I think it was the "Nealy" brand over the web http://www.tirerepairkit.com/) and fixed it my self in the garage. I had a air compressor at the house. It's been fixed for 6 months.
I kept the kit and some basic tools (pliers, gloves, rag) in the car. When I put my snow tires on I got to see the patch from the inside. It's just like they said in the repair kit, there is a knot on the inside of the tire with the patch going though to the outside. I'm very happy I could fix it.
I had owned my passion for three days when I got in it to go to work and the tire inflation light was on. I immediately assumed it was a malfunction, but I noticed the car "felt funny." So, I got out and checked, and I had picked up a screw in the left rear tire, and it was totally flat.
I have a tire repair kit at home, so I got a crash course that morning in jacking up the smart, and that's when I learned we only have THREE lug nuts!
It felt WRONG to ream out a hole on a brand new tire to insert a plug repair strip, but that's what you've got to do to fix it!
When i had my car three days I noticed the right rear tire was half flat. I put air in it and was able to drive to the only place I could find open on Sunday. They were able to show me a piece of metal in the inside sidewall and they had no tires in stock. They put more air in and I drove home. On Mon, put more air in, went to the dealer and bought anew tire. I was lucky the leak was slow. I also bought a jack and a Neeley tire repair kit. Eventually I'll get a spare, I like to be self safucient
I always keep a plug kit in the cars with me. I haven't used a temporary tire on a car in almost 20 years. The moment I discover the flat, I pull out the nail or screw and plug the hole right there on the spot. In my other cars I've always carried a portable compressor. You just need to carry needle nose pliers, a flat head screw driver and a phillips head screw driver. All of those should be able to pull out whatever caused the hole. If you get a hole in the sidewall, then it's time to call smartUSA to tow the vehicle to a place to get a new tire.