2012 PIP GPS ETA defect

OK, but now I wonder, is this a recent change? Did the nav ETA used to be accurate? I notice you joined PriusChat in 2013. Are you the original owner? If not, I'm wondering if another smartphone might be linked, and affecting the time. I quit using Entune when it didn't want to release my phone when I left the car. I have a different phone now, but had to go in manually to remove the old one from the system.,

 

This is really out in left field!
Did you happen to replace your 12 volt battery? or disconnect the battery at anytime?
If so, did you reset the date calender to the correct date?
what if the car thinks it is Jan 10, 2013, would the clock be off??? by an hour?
Just really grasping at straws!

If you want to check out your date.
page 275-276
Instrument cluster
setting up displays
calendar

 

I understand not the car's clock, but I thought maybe the cars date, the car would still think it was winter instead of spring and be a hour behind. Oh! Well I did say out in left field!

 

I applaud your persistence and hope you get a satisfactory resolution to this issue. I agree its not a big deal but that it should be fixed, no matter how small, especially considering Toyota doesnt even know how to fix it.

I'm still kind of thinking there was a setting in there somewhere during some old firmware revision but has since disappeared. Maybe this will make Toyota bring it back in a future firmware update. What if a PiP owner lived in a state that borders another state that does not observe DST.. how does the nav system know one way or the other.

 

Hmm.. looking at the parts diagram, the only thing that sounds like it might fit the description is the DCM (Telematics Transceiver).. although I have no idea what that thing does, never even knew it existed

Cant post a pic right now for some reason, but it looks like a little box that is located behind the dash, underneath the nav head unit

 

Sounds like they are finally getting to the bottom of this mystery. I hope the fix works for you.

 

Just for an update on the "how the GPS knows the time", that's all GPS is. I have little hope for replacing a magic box and hoping the problem will go away.

GPS is just a bunch of satellites that transmit their time. The time is the same on every satellite and produced by onboard atomic clocks that are re-synchronized regularly (if they ever need it) to be ultra precise. You then pick up at least 3 of these signals. Each frame you pick up from the satellite says which satellite it is and what the time was when the packet was sent. Knowing each of the times you can then figure out how far away you are from each of them and therefore your position.

This means your GPS unit knows what time it is. If it did not, the "P" in your actual GPS would not work at all (P = position). The caveat is that the time it knows is Coordinated Universal Time (UTC). UTC does not use daylight savings. Being in NJ, you are UTC-5 when you do not have daylight savings and UTC-4 when you do have daylight savings. Considering we are now in that mode, I maintain that I think the problem is as simple as the wrong time zone.

You should be in EST (Eastern Standard Time) for the times you are not in daylight savings and EDT (Eastern Daylight Time) for the times like now. Otherwise your GPS will always read UTC-offset. If programmed to be EST, it will always read UTC-5.

 

Congratulations on your persistence. I have to admit to being one that doubted that you actually had a hardware problem and thought it had to be a setting problem.

 

It is still a bit of a mystery to me.
How can there be a "hardware" component problem that creates a symptom of exactly off by an hour?
Seems more likely to fail to connect or some other large failure rather than one tiny error of off by exactly an hour.
It is hard to imagine that (as a wild example) there is a connection to read the DST on/off and this one connector it failing to read that value correctly. It is also hard to see how there could be some firmware in that device and everything about it is OK but it has a DST on/off bug that no one else has.

I'm not doubting anything about what is being reported, etc. But it is very strange.

Mike

 

Even in my 2004 BC with Nav, there was a Time of Day setting under the settings (separate from the clock), and on my 2011 Five with Nav, same thing (plus, IIRC a "Daylight Savings" button). I suppose that if the software was expecting a heartbeat or interface to another system on the bus, it's possible the menu wouldn't display the option. Very odd.

 

Actually, I worked on the software in the Space Shuttle and had to deal with the IRIG-B time signal between computers. It produced the official MET (Mission Elapsed Time) and was the most accurate timing signal for syncing various operations. But during ground testing it failed many times (loose wiring, accidental reset by a human button pusher, etc.) causing defaults back to other timing signals which caused all sorts of "glitches" which caused many tests to have to be rerun -- until I designed a glitch detector between all the clocks to prevent that.

Mike

 

Interesting, Mike. They needed your expertise in the Obamacare rollout- plenty of glitches in that one!