Every Focus (US and Canadian) should have the TPMS sensors. If you have the sensors already installed in the wheels you can change the tires out youself but the onboard computer will need to "re-learn" the new sensors. This could be done at the dealer with their little tool or you could pick one up from us - Ford Trigger Tool
- and train them yourself. If you already have one of these tools shoot me an E-mail because they don't come with instructions, I can get those right out for you.