So, I have been all over the Internet trying to figure this out. I haven't had much luck with it. I just bought it about 3 weeks ago, and it started either the first or second day. The TPMS light along with the security light come on, for no reason. I can't reproduce the problem if I wanted to. It's always both of them, never one or the other. It's like it has a mind of its own, there's no rythm to it. They don't steadily blink, just on, maybe 2 or 5 seconds, then they go off. Could be 3 seconds or 10 minutes before they decide to come back. I do not have a model that has a security system. Just the little key with a chip, no fob or anything. The tire pressure seems just fine for the tires. Manual locks and windows. Any help is greatly appreciated. It's driving me crazy.