A few times I've come across posters mentioning a "hard" reboot vs a soft or normal one. Some go to painstaking detail in outlining the crazy voodoo steps required to engage this magical hard reboot. Some even purport to say there are times when such a reboot is "necessary".
I say it is all nonsense. [skip to end for a short version]
Here's a particular and recent
thread on the subject (different forum, sorry) where you'll see several people explaining that there's a difference. One even links
to a different thread, presumably as evidence that there is in fact a difference... but that thread contains more of the same: pure conjecture and a bunch of - I believe - nonsense. There are many MANY other threads, blogs, etc all spreading the same [mis]information.
The general "consensus" seems to settle on two different ways to achieve the same magical state: 1) Press the brake... no wait, press it "hard", while doing the common reset and you'll do a "hard" reset; 2) hold the reset switch down for 20, no 30, no 45 seconds to get to the "hard" reset.
Neither of these made much sense to me, but both were plausible. First, the time component: We've all had experiences when some low-tier tech support rep at our ISP says to unplug the router and wait 30 seconds, so that must be how to do it right? The time element is ONLY to clear a capacitor, ensuring power has fully been turned off. Once a reset is triggered, it is triggered. You can't trigger it "harder" by holding it down longer. Now... it is possible to trigger a true hard reset by having the button pressed at the beginning of a power on vs. while powered on, so holding it down through the complete cycle *can* make a difference. But does it on the Tesla? We'll see. As far as the brake goes: pressing it hard vs. not had to be complete nonsense, but it could be possible that the brake is a secondary hardware input signaling the computer to do a "hard" reset vs. a quickie... to me that made little sense because if there truly is a difference between "hard" and normal resets, surely they'd want a less conspicuous trigger than something you probably press out of muscle memory whenever you're sitting in the driver seat and not driving. I mean, if there REALLY is a difference, they don't want you doing one vs the other all willy-nilly, right?
But... I'm not one to put my thoughts as correct and others as nonsense without at least SOME experimentation, so that's what I did.
In all my years working with electronics, I have never ever EVER experienced a system where one type of startup vs. another didn't affect the time to some degree. For example, you do a soft restart of your Windows system vs. a full power down, power on... one takes longer than the other, right? If you unplug your router and plug it back in, that takes a different amount of time than if you do so while holding the reset, right? A "hard" reset is simply going to take longer than a soft one... right? If we can't agree on that, then you're dismissing my entire premise so no need to read on.
I went out to my car with stopwatch in hand. I engaged the reset of the instrument cluster (holding down both buttons above the thumbwheels) without the brake pressed and the display went down at 14 seconds. I immediately let go. The display started back up 11 seconds later and was fully on 4 seconds after that. I repeated this TEN TIMES, because if this wasn't consistent than there was no way I could convince myself that witnessing a "hard" reset was or wasn't real. It was precisely consistent, with each and every one taking the same timing plus or minus half a second. Then I repeated it with the brake pressed with normal pressure... same result. Then I pressed the brake hard... same result. Then I pressed the brake SUPER HARD - just in case that really was the trick... same result. No variance at all. There's no way a magical "hard" reset was being performed. Then I tried again but this time I never let go of the buttons. Again, the display went out after 14, on 11 later and fully on 4 after that... I continued to hold... for 5 boring minutes. Nothing. That was simply 5 minutes I'll never get back. Myth busted. I then repeated the same nonsense with the 17" display (holding down both thumbwheels). This one resets after only 4 seconds, takes 21 to come back on and another 12 to be ready to rock. Brake, no brake, hard brake, keep holding... no variance whatsoever.
So then out of curiosity I decide to do a real factory reset. To me, that's a "hard" reset. Because if that too took more or less the same amount of time then maybe I'm wrong and maybe hard vs soft just doesn't make enough time difference to notice. The funny part is that I didn't want to inconvenience my wife to reset her profile, so i put it in her profile before doing the reset. Now let me set the stage for you: I'm 6'4 and closer to 300lbs than I'd like to be. My wife is 5'1 and a tiny little thing. So here I am contorting myself as best I can with her profile squeezing me like a grape while I do this reset. I'm thinking instead of the 30 seconds or so that it might be a minute. No such luck... I was smashed up for over 6 minutes while it did its thing. Now THAT is a hard reset! Lest you think that there's actual demons in the box that have to paint over the memory sections one stroke at a time... that isn't explained simply by settings getting deleted. Deleting settings happens in nanoseconds. That time difference has to be due to a complete kernel reload.
Conclusion? Yes, there is a "hard" reset. No, it isn't dependent on how hard (or even if) you press the brake or whatever other nonsense voodoo. Its right in the settings screen.
Am I wrong? By all means, prove it.
[TL/DR Version]
- Instrument cluster takes consistent 14 seconds to engage reboot, 11 seconds to power back on and 4 seconds to normal state. This is regardless of whether or not brake is pressed or buttons held extended time.
- Similarly, 17" display is 4 + 21 + 12. Again, no difference with brake, etc.
- Factory reset takes several minutes.
- Conclude that no "hard" reset exists, other than the factory reset.