Clock Operation and Daylight Saving Time feature

[Stan Ames]

As we drive across country in our new Prius 5 I notice that the clock on ths dash display is just a dumb clock and does not change as the time zone you are in changes.

On the NAV display there is an option for timezone and daylight saving time.

The strange thing is that the time to get there on the NAV also does not change with respect to timezone and you must change it manually each time you change a zone. (which is a poor design for a GPS system who knows where it is.)

So my question. What does the daylight saving time function do.

I see no place to enter the date so what effect (if any) does the daylight saving time setting actually do?

Stan Ames

[qbee42]

When you say "Time to get there", do you mean ETA or ETE?

Tom

[Blind Guy]

Originally Posted by Stan Ames

As we drive across country in our new Prius 5 I notice that the clock on ths dash display is just a dumb clock and does not change as the time zone you are in changes.
* Agreed, most modern GPS's receive their time from the GPS satellites, and therefore the time is accurate to miliseconds. When using this type of system, the satellites know where you are continuously, and update the clock as you travel from Time Zone to Time Zone.
On the NAV display there is an option for timezone and daylight saving time.

The strange thing is that the time to get there on the NAV also does not change with respect to timezone and you must change it manually each time you change a zone. (which is a poor design for a GPS system who knows where it is.)
* Also agreed.
So my question. What does the daylight saving time function do.
* Permits the clock to automatically adjust to DST on the appropriate dates.
I see no place to enter the date so what effect (if any) does the daylight saving time setting actually do?
* You simply select Daylight Savings Time ON/OFF, and it will automatically change the clock on the correct dates (it will advance or retard the clock 1 hour from whatever time you have set, whether those times are right or wrong!
Stan Ames

David (aka Blind Guy)

[32kcolors]

The clock doesn't automatically change when daylight saving time kicks in, so you toggle the ON/OFF switch to display the correct time.

[Stan Ames]

Thanks for confirming my observations. I was hoping that somehow I had just missed something simple.

We are just about finished with our coast to coast trip in our new phase 5 Prius and our general conclusion is that the drive train and overall car represents the top end of technology but inside the electronics are a tad in the dark ages.

Stan

[Jon S]

I can't think of any car that will change the clock's time according to changes in the zones you drive in...

I can't even think of a watch that does that either...

[RodJo]

Originally Posted by Jon S

I can't think of any car that will change the clock's time according to changes in the zones you drive in...

I can't even think of a watch that does that either...

The Navi knows the current time AND consequently your location. It shouldn't be that hard to do the conversion and display the local time (and date).

[Tideland Prius]

Originally Posted by RodJo

The Navi knows the current time AND consequently your location. It shouldn't be that hard to do the conversion and display the local time (and date).

Do any Garmins do that? My TomTom doesn't change time when I'm in another time zone.

[dc202]

Originally Posted by Jon S

I can't think of any car that will change the clock's time according to changes in the zones you drive in...

I can't even think of a watch that does that either...

My Honda NAV does this.

[nylion]

Originally Posted by RodJo

The Navi knows the current time AND consequently your location. It shouldn't be that hard to do the conversion and display the local time (and date).

It's not as easy as you think. The time zones do not follow straight lines. There is a lot of zigging and zagging to accomodate county and town lines, bodies of water, etc. I know someone says his Honda nav does that, but that's surprising. GPS works on Universal time (GMT). The local device (your nav) uses your setting to add or subtract the rigth number of hurs from GMT. The daylight time adjustment is a convenienc that just adds (or subtracts) an hour when you set/unset it.

I agree that it is disappointing that the clock display doesn't get its time from GPS. In my old Acura the time was displayed on the nav screen, so it was always correct time. GPS time is extremely accurate. The standard clock in my Prius keeps very good time. Like most modern electronic clocks, it doesn't seem to gain or lose more than a second or so a month. Since it doesn't have a second display, I tell how my clock is set by listening to NPR on the hour and noting when the "All things Considered" theme starts. That is always going to be no more than a second past the hour. So far my car's clock is right on.

BTW I maintain a public time service for computers (tick.mtnlion.com). Some very large companies use it as their time standard. I use software (NTP) that gets the time from about 10 sources. Some are atomic clock based, and some come from GPS. It is accurate to about a ten-thousandth of a second.

When I drive, I like the clock to be accurate within a minute. The standard clocks far exceeds that expectation.