I know that every few years, some sort of "Prius as an emergency backup generator" thread gets traction. I have a good handle on the various versions of that, but one thing that I don't think has ever been fully solved, is the security problem it can create, depending upon your location/situation. This thread is an attempt to resolve that. As an aside, my own motivation to solve it, and to put in some real work on it, is not primarily for when using my Prime as a house-backup generator. It is actually for a couple of very different scenarios, with the exact same security problems, and presumably the same solutions. I'd be happy to start threads on the two other scenarios I'll use the solution for, after solving this. But for now let's just view this thread as an attempt to definitively solve the general problem: "Theft Prevention for a Prius Prime Left in Ready Mode" The situations where I've badly needed the above solution, have usually (but far from always) been in places where I was semi-comfortable with the easiest solution: SOLUTION #1: Close up the car, lock it using the physical key in the driver's door, and take the key and all fobs with you when you leave the car unattended. Pros: It disables the key fobs and disables touch unlocking. You need to use the physical key to open it. Very easy. You have the option to make it look like you may be (living and/or sleeping) in the car. In some situations, that will discourage a breakin. In some situations, that will encourage a breakin. Cons: Someone can break in and drive the car away. They could drive it anywhere, not that a typical car thief takes it far. SOLUTION #2: Solution #1, plus a Denver Boot type device on a wheel. Pros: It disables the key fob and disables touch unlocking. You need to use the physical key to open car. Still easy enough. Cons: Need an industrial-strength boot, otherwise same cons as #1, just delays them. For situations different than generator, keeps you from leaving quickly. SOLUTION #3: Lock shifter from working. Many different designs possible, with different pros/cons. Likely Pro: Car remains Ready, house remains powered by car, car can't drive. Simplest idea, let the car be Ready, but unable to get power to the wheels. Some ways are physical, some are kill-switch-like, some are key-switch-like. I think the better ways of doing it are easy to make work, hard to make truly secure. The easier ways might stop 80% of car thieves. Maybe a combo of easy ways would stop 95%. Hard ways might stop anyone but a Toyota tech. SOLUTION #4: Kill switch on high voltage line to MG2. Pros: Pretty badass solution if it works! Cons: Can't kill-switch MG1 also, because MG1 charges traction battery. I think car can operate as HV without MG2, with MG1 being what ICE pushes against? SOLUTION #5: Have thief's presence turn off ignition, making car no longer Ready. Pros: Could be pretty simple alarm/relay, and if it works, extremely secure once tripped. Unlike seeing a key/kill switch to try to defeat in #3, he has every reason to leave. Alarm could also trigger horn/siren/etc. Cons: Basically none, it puts thief in same position he'd be in after breaking into a random car that's off. I guess you'd end up with a drained 12V battery if your inverter to house runs with ignition off. So it would be wise to have a relay to only power your house when ignition is on. SOLUTIONS #6-#100 Things you think up. SOLUTION #101 Some foolproof combination of the above that evolves from this.
For my own home, sure. But it's not nearly as portable as a Prius, say you want to go power up a relative a 5 hour drive away using the car. My own main uses for generator-mode security are not at all for a generator. It is for leaving my car in Ready Mode to run climate control when I'm doing stuff like hiking all day in 100F heat, and want the car to be cool when I get back, and also give the freezer under my pillow a chance to still be alive, rather than fighting a 150F car interior temp all day. Or for many people, it could be leaving their dog in the car with AC on while they grocery shop or go into a laundromat when it's 115F out. There were a couple of times when I left my Prime in Ready Mode 24/7 for a month at a time, except when pumping gas. Though generally in very safe places, not always 100% safe, so I had to choose between turning the car off for an hour, versus worrying that someone would break in and drive it away. First world problem, I know, worrying about killing my car freezer, or having to wait 20 minutes for a boiling car to cool off after a grueling but totally optional day of desert Southwest hiking.
I strongly suspect the car won't like that at all. If it doesn't discover the interrupted continuity right away and code, it probably will the next time it goes to start or stop the engine, because I believe it does apply some MG2 countertorque to help reduce the rocking of the car on engine start or stop.
Car thieves around here will load it up on a wrecker and be gone in minutes. Does not matter if it's in Ready or not. It primarily matters if the chop shop needs your parts. Trusting that nothing goes wrong is liable to kill the dog one day. Would you leave a child unattended as well?
The dog example was not about me personally, but was just mentioning what is beyond any doubt by far the biggest reason that other leave a Prius in Ready mode while they run errands away from the car. At some point, it pays to recognize the reality of how people actually use their cars, when discussing an issue about how to help them best do so. I don't have a dog, nor any minor children, and no, I don't leave a grandkid unattended in my car. Unlike people who car camp in a Prius, or even LIVE in a Prius with a dog or two or three, I am able to bring a grandkid into the grocery store with me, or a restaurant, or a casino, or a shopping mall, or a doctor's office, hospital complex, or wherever. People going to the dentist, who are living in their car with 3 dogs, don't have that option. They lock the Prius manually, do their thing, and return to dogs who are perfectly fine. They typically have a "pet monitor" which sends them text/email alerts if the temperature in the car goes out of their chosen comfort range. Waggle is one brand of those.
Remove a tire and store it behind a front seat and take the lug nuts with you. Might need a jack stand or two, but that also might make it easier for a thief if they have wheel(s), lugs and a jack with them.
Focus on method #1, it's simple and not even inconvenient. From there on down, you're overthinking it.
Simple is always best, IF it meets all the needs. I wish it was still as easy as it used to be to stay fairly safe while online without having to think to hard about it. Stuff is gettin darned right these days, it seems, at almost all levels.