Let's get the "owner is a bad person" stuff out of the way up front...Due to multiple dui offenses, I had to have an ignition interlock device (IID) installed on my 2006 pkg. 3 in order to be allowed by California to drive. Please take it as read I regret my actions and I am doing all I can and all that I am required to do make amends for my past wrongdoing. Unfortunately, none of the three Los Angeles device installers is a Prius tech. Of course, when I asked, all three companies said there would be no problem for their contractors to install their device, so I went ahead and picked one and got it done. (Lots of red flags should have gone up for me--I guess they did, but I was so anxious to be driving again, I ignored them.) The company I went with is called Guardian Interlock. Their local installer seems nice enough. He ran into problems with the installation, but said he got copies of schematics from a Toyota tech friend, so he'd be able to ensure he wasn't linking any wires anywhere they shouldn't be. I paid LOTS extra for the extra time the installation took him over standard installs. Anyway, within less than 100 miles of installation, check engine light (CEL) came on. Again, note that the IID installer is not a Prius tech, but he checked the code for me, which he said was P0172 - System too Rich (Fuel Trim). He reset the code, but the light came back on within a couple of miles. I then took the car to a local repair shop with a real Prius tech, who ran full diagnostics, and came up with 17 or 18 codes in addition to P0172 (u0293 host communication with hybrid control system malfunction, u0073 voltage problem in airbag communication system, o0121 control module communication bus off, no communication w/ abs control system, right and left front air bag sensor errors b1615 & b1200, smart key control module communication malfunction and others). The tech said he could not reset the codes (he tried, but it didn't work).When I went to start the car to take it back to the installer, the big triangle with the red exclamation point was on. On advice from Prius tech, I had the car towed to the non-Prius tech Guardian installer, who is examining his installation for errors. The installer is just a contractor for Guardian, and he's in a bad spot, too. He has put in a lot of time here. I spoke with a couple of reps from Guardian itself about another (!) issue, and one was very nice but non-committal. The other was rude and obstructive, and told me, basically, any problems are mine, he's not interested in helping me, and too bad about that little legal issue from California that says I'm pretty well stuck with them if I plan on driving for the next couple of years. I'm upset and confused. There's no consumer agency that I can think of that can help me work through this and I don't know what I'll do if there is, in fact, damage to the computer systems. I don't know for sure, but I suspect that Toyota won't fix any damage caused by this escapade, since it was caused by an aftermarket installation. (The car is still under warranty--32k miles on the odo.) I don't really know what my question is...I'm just trying to get SOME kind of feedback, so I have some ideas of what to do/say as this nightmare continues to unfold. Please, I beg you, suspend your judgment on what I did that got me here, and give me constructive thoughts on this. I'll answer any other questions that'll help--I've just tried to give the pertinent info here. Thank you.