Author Topic: Check your GPS date and time  (Read 698 times)

Kremmen

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Check your GPS date and time
« on: January 04, 2022, 01:21:45 PM »
It's been reported on the Civic forum that there may be a problem with older GPS auto date/time :

It seems that some older cars GPS auto dates have broken. Honda Civic 8G SatNavs are suffering and some others are as well that are based on Alpine software, maybe others as well.

It seems that some older units have 10bit systems.

Here are the calculations:

10bits = 1024 values
1 value = 1 week
1024 weeks = 7168 days
Some Honda/Alpine units have a base date of 20/05/2002
Add 7168 days = 03/01/2022

..... So now they are beyond 03/01/2022 the GPS date and time is one hour wrong for some reason and showing 2002.

« Last Edit: January 04, 2022, 01:25:24 PM by Kremmen »
Let's be careful out there !

nowster

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Re: Check your GPS date and time
« Reply #1 on: January 04, 2022, 02:53:07 PM »
Initially, I thought it was GPS week number rollover again.

https://en.wikipedia.org/wiki/GPS_week_number_rollover

It's possible that it considers all week numbers above a certain number as being from 2002-2019, and all those from zero up to that threshold being from April 2019 and after.

Because May is in summer time, the time will be out by an hour.

culzean

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Re: Check your GPS date and time
« Reply #2 on: January 04, 2022, 03:00:58 PM »
Wot, a satnav computer millennium bug ?  Maybe Doctor Who's Tardis crashed into a satellite and turned it into a time machine... such fun.
« Last Edit: January 04, 2022, 03:03:02 PM by culzean »
Some people will only consider you an expert if they agree with your point of view or advice,  when you give them advice they don't like they consider you an idiot

Kremmen

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Re: Check your GPS date and time
« Reply #3 on: January 04, 2022, 03:14:02 PM »
Apparently Honda USA have acknowledged the problem and have said there may be a fix by August !!

Honda USA 

Quote
We have escalated the NAVI Clock Issue to our Engineering Team and they have informed us that you will experience issue from Jan 2022 thru August 2022 and then it will auto-correct. Please be assured that we will continue to monitor this and will advise you if a fix is available before that time.
« Last Edit: January 04, 2022, 04:52:56 PM by Kremmen »
Let's be careful out there !

RichardA

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Kremmen

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Re: Check your GPS date and time
« Reply #5 on: January 08, 2022, 11:10:02 AM »
From Civinfo it's looking like every 8G (Spaceship 2006 - 2011) with a GPS controlled clock is affected. These were the Honda / Alpine units with the mapping on a glovebox DVD.

The later Honda Connect / Garmin units should be OK.

What I can't determine from Honda USA's input on the CRV site is whether Honda are working on a fix by August or whether they reckon it will auto correct in August.

I find it hard to believe that with the Y2K bug that cars produced after 2000 have a similar problem with the century being omitted from the working storage.
« Last Edit: January 08, 2022, 11:19:41 AM by Kremmen »
Let's be careful out there !

nowster

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Re: Check your GPS date and time
« Reply #6 on: January 08, 2022, 12:23:40 PM »
I find it hard to believe that with the Y2K bug that cars produced after 2000 have a similar problem with the century being omitted from the working storage.

It's nothing to do with the century, but everything to do with GPS week number rollovers, which reset every 1024 weeks (roughly 20 years). Some programmer will have known about the 2019 rollover and programmed for it, but the workaround (if weeknum < X, add 1024 weeks) went wrong when the week number went over the fudge factor number.

The fix itself is trivial (always add 1024 weeks) and will work until about 2038. I don't know why it would take them until August to deploy it.

RichardA

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Re: Check your GPS date and time
« Reply #7 on: January 09, 2022, 11:27:34 AM »
From Civinfo it's looking like every 8G (Spaceship 2006 - 2011) with a GPS controlled clock is affected. These were the Honda / Alpine units with the mapping on a glovebox DVD.

The later Honda Connect / Garmin units should be OK.

What I can't determine from Honda USA's input on the CRV site is whether Honda are working on a fix by August or whether they reckon it will auto correct in August.

I find it hard to believe that with the Y2K bug that cars produced after 2000 have a similar problem with the century being omitted from the working storage.

Mk2 Jazz T grades (EX-T, etc) were fitted with sat nav.
Mk1 Jazz was never offered with sat nav unless Honda offered a dealer-fit system.

The latter would almost certainly be affected if such exists, the former probably as there is overlap with the 8G Civic, but I don't know if its Alpine or Garmin-based.

Kremmen

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Re: Check your GPS date and time
« Reply #8 on: January 09, 2022, 12:59:32 PM »
The Civic did have a T grade but, it wasn't the standard built in DVD based unit.

It was basically a Garmin PND bolted to the dash top but linked to the car.

 
Let's be careful out there !

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