Hi, I own a 2008 Scion tC 1G. A few months ago, I broke the key in half. The transponder chip wasn't damaged at all, it started fine after that and still read to the car. The next morning it wouldn't start. For all of this post, the car cranks but does not start, but will even fire a little bit, almost starting sometimes. Right before this happened, there was also a gas smell around the car a lot. My dad, who is a master technician, looked over my car and determined it to be a bad ECM, which made a lot of sense since it had a p0606 code for the longest time. The ECM was replaced, programmed properly with an OBD connector for 30 minutes and everything, but the car still wouldn't start. So, he reprogrammed the key I had to the car with the thing where you open the door so many times and hit the buttons a certain way and it would make the anti theft light turn off and every but it still wouldn't start. But, my dad went in and found B2799 code and key code in the car and said the car needed a new key programmed. So, I got the car towed to a locksmith for them to tell me that the key was reading just fine and they repaired the broken in half key for me and sent me on my way. So, by now I'm thinking it must be something else, so I get the car towed to a local shop. They said they were having the same key code, and they said the car actually needed 2 registered master keys for it to start, so they said they will get 2 new blank keys and start over. After doing that, the car still wouldn't start, they checked every single wire, and they said it was because there was no communication between the immobilizer system (transponder ECU) and engine ECU. But, after that they didn't actually give me the 2 keys they programmed and gave me the original they unprogrammed. So at this point, with the original key (the one that was broken in half and repaired) now doesn't turn off the anti theft light like it used to after going to them. The light doesn't flash when the car is locked and it stays solid red when the key is in. So I got it towed to toyota because I was done and just wanted to get them to deal with it because they made the car you know? Well, they said I had "mismatched" ECU's and they were all bad and had to be replaced, that and 2 new master keys was $2800!!! I decided that I was definently not paying that, and asked them just to program the master keys for $500. They said they couldn't do it because the computers were mismatched but keys had been programmed to it recently perfectly fine so I couldn't tell if they were just trying to get money from me or not. Anyway, I paid there diagnosis fee and got it towed back home. I ordered two blank keys from amazon with the transponder chip needed that look identical to the original key, because I know you can program them yourself with the door opening and closing method. But, I don't know if that will work because you need a master key and I have it but I don't know if it is properly programmed or not. Now I'm stuck, with the original key, which was the master key, with the security light not blinking and it will only light up and stay solid while the key is in, and that is all it will do. I have looked everywhere trying to figure out what to do and have gotten nowhere and I can't afford anymore locksmiths or dealerships or mechanics or anything like that. If anybody can help at all I would really appreciate it