Folks i am sorta a nerd myself, more interested in the electronic side of this than the business side. I have been where those poor toyota technicians are , you spend days and nights watching bus traffic on a logic analyzer busting your brain what's going on and why one in a zillion instructions fouls up. It's life changing and you'll do thirty hour shifts to fix it. And I only had a power plant simulator at stake not the life of my company...hence my feelings for those techs.
That aside, last night i emailed my daughter who owns a Sienna and her hubby a Scion. What i told her to do is get on an isolated stretch of road, stop the car, then floor it and practice turning off the key and bringing it to a stop . Several times. That way she'll get the feel for brake pedal with no vacuum boost and, if those electronic transmiisions don't keep wheeling the engine like old mechanical ones do she'll know what powerless steering feels like. I told her do it several times so you get habit of do not turn the key to LOCK... that'd be danger of shifting into neutral - if in your excitement you turned off key you'd likely go through OFF to LOCK and hit a tree...
I'd suggest you think about that, Selma. The odds of malfunction are miniscule but the consequences horrific so that ounce of prevention is leveraged into good investment. But then you seem mighty sensible, so just being aware may be adequate for someone of your obviously calm composure.
Just to know what i have myself a couple days ago I turned off key in my 92 Oldsmobile going down a long hill. Transmission keeps the engine spinning so there's power steering and vacuum for the brakes. I guess it's not an overly electronic transmission.
btw when you lose vacuum boost it takes a LOT more brake pedal pressure than old fashioned non-power brakes.
I learned on my Ranger that they use a different pedal for power than manual brakes, the fulcrum is in a different place so you have less leverage. The shop manual mentions it and i looked, sure enuf the brake pedal itself is stamped on the side AUTO or MANUAL and the master cylinder is mounted higher on non-power to align with fulcrum...
That's the reason people report brake failure with this malfunction. it'd take Arnold Schwarzenegger legs to overcome an engine that's still in gear with wide open throttle plate - it has no vacuum to boost your brakes BECAUSE the throttle is wide open!!!!
Now that's dominoes stacked up for you - a single failure that applies full power, takes away 90% of your brakes, and leaves no trouble code. That's why early ones were chalked off to bad driving no doubt.
As i told Dai - excess caution has spilt over into my home life. Sorry if this comes off as dead horse flagellation.
be safe guys. And I still like Toyotas. But still my most beloved vehicles have been Chryslers, a '62 Newport and that '95 Caravan.
and i think that's all i have to say ...
over and out, a.
Cogito ergo doleo.