Anyone else find the clock is fast on their 2010?

Yeah Set mine with the cell phone every 3 months or so! Don't know if its a Toyota trait or what! my Toyota Yaris does the same thing.

 

Drive faster; that will slow down the clock.

Tom

 

haven't noticed, but maybe it is... my wife has the habit of having our alarm clock 10 to 15 minutes fast and her car 5 or 10 minutes fast... I thought she had gotten to my car as well.. Maybe the bugger was just fast... have to check that out!

 

But we can always save a few pennies by making it a little less accurate.

 

I noticed the clock in my Prius is about 5 minutes faster as well...I thought it was the dealer whom set the clock incorrectly.

 

I tried that, but the red and blue shifts seem to converge in the mirrors.

 

Prius is just ahead of the curve. Next month, home electric clocks will speed up too:

Power grid change may disrupt clocks, traffic lights

 

had to reset clock the other day and it was several minutes ahead. Same with Dodge, so don't thinks it is Toyota only issue.

The lower temperatures make clock run faster due to quarts thermal expansion.. Perhaps Toyota clocks are tuned to higher avg temps?

 

On a tour of the PJM Interconnect many years ago, I learned that grid frequency is already being adjusted (e.g., boosted ~0.5Hz overnight) to help keep the system in sync, so this isn't new news, unless the magnitude of these adjustments will be changing.

 

:dance:
Thank you, Prof. Einstein! ... relatively speaking, of course.

 

That is the point of this news: the magnitude of the adjustments will be changing sharply:

 

I saw this on myway today! My Way News - AP EXCLUSIVE: Power grid change may disrupt clocks
my battery clocks in the house run fast also.

 

Actually, it's not just the magnitude: It's the average value. Cycle-to-cycle time on the 60 Hz grid has never been very good (speaking as a person who actually worries about +-1.6e-8 variations in clocks in his day job), but the long-term average clock has always been purposely nailed to the National Bureau of Standards banks of Cesium clocks, Hydrogen Fountains, and other esoteric means of Knowing Just What Time It Is. Hence, that $5 cheap-as-nails alarm clock/clock chip that monitors 60 Hz power in order to keep track of time has been just as accurate as the NBS, at least for waking one up in the morning. Now all these manufacturers will have to invest in a $1 oscillator to get something reasonably accurate. For people who worry about the numbers of tenth of a cent surface mount resistors, that's a major expense. Since, natch, that $1 oscillator will probably ending up being around 30% of the total cost of the electronics.

Now they're going to permanently unlock the system clock and leave it that way. That gets rid of all the tedious mangling around with the phase over time to get back in sync with the NBS, which is probably what they're really after, but it means that gazillions of alarm clocks and such could be (worst case, not likely) off by 20 minutes or so after a year of this.

So, given that I'd bet that 20 or 40 million power-line style clocks get sold in a given year, we'll all end up spending $20 or $40 million bucks a year over time to end up with semi-accurate alarm clocks, the power companies will save a couple million or something not having to keep the power clocks locked, and that will be that.

KBeck

 

20 minutes/year worst case is still about as good as you will get with a cheap consumer level crystal and assembly line tuning in a clock.

For those who want more accurate time, cheap WWVB clocks seem to be good out to around 1,000 miles from Ft Collins Colorado.

 

The same: 2 days ago I had to roll back my clock 5 mins. Strange, huh???

 

Stop using Pulse & Glide.

Tom

 

2 minutes and 8 seconds over 3.5 months is actually pretty good; that's only 14 parts per million off. Probably the most common oscillators used are rated for around 50ppm - though to be fair, the Prius very well may have a 50 ppm oscillator, but because it's not being subjected the most extreme conditions possible (according to the oscillator specifications, anyway), it's performing better than that.

There are a lot of things that will affect these oscillators; temperature, voltage, age, vibration, acceleration... And cars are not known for being well-controlled in any of those aspects.

Now in general, these effects can be compensated for in a variety of ways. But doing so makes the oscillator bigger (a few mm to as much as several inches or more), more expensive (do you want to pay an extra $10-$100?), more power-hungry (and who wants their 12V battery to die because it was keeping time?), etc.

The best way to keep accurate time is really to use a broadcast signal; this is what most cell phones do, though it depends on the cell phone company having the right time. It can also be pulled from one of several low-frequency radio broadcasts; WWVB in Fort Collins, CO covers most of the continental US, DCF77 covers a large amount of Europe, and there are others elsewhere. GPS signals contain accurate time information as well. Unfortunately though, each of these options costs money, adds complexity, and may not even work well - for example, the low-frequency radio stations often can only be received late at night, when the car is likely to be in a garage surrounded by a lot of house, and the signal may not be strong enough for the car to receive it.

So yeah, they can make a better clock, but for most people, it's just not worth it.

 

16 nanoseconds? That's ages! My work is generally more concerned with picoseconds, usually up to no more than a few hundred of them at a time. (A picosecond, or 0.001 nanoseconds, is enough time for light to move 0.3 millimeters, at most.)

 

I don't allow ordinary surface mount resistors that expensive to stay on the bills of material I review.

And in some applications (past for me, not present), even a picosecond is hideous phase noise.