Government safety warning, Furuno gps.

Stemar

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The Maritime & Coastguard Agency would like to make operators aware that products with Furuno Global Positioning System (GPS) chips for position or UTC (Coordinated Universal Time), may produce an error on January 2nd, 2022.

So, does that mean they'll be fine again now, or is it an ongoing thing? Oh, well, I guess I'll have to try mine and see what happens. If the error puts me on the wrong side of the world, it's a pain, but not dangerous. If it's a mile out, it could be.

Added - more info here Important Notice | News | FURUNO

And it seems to be permanent - with some exceptions, if I've understood the Furuno site correctly, with some exceptions, if your kit is affected, it's toast
 
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AngusMcDoon

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I don't know details of the Furuno problem, but a similar issue with an old Garmin GPS45 it now gets the date wrong persistently but the position is always correct. This means that I know exactly where I am when I run aground because my tide calculation was bullocks having used an incorrect date.
 

Sandy

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I don't know details of the Furuno problem, but a similar issue with an old Garmin GPS45 it now gets the date wrong persistently but the position is always correct. This means that I know exactly where I am when I run aground because my tide calculation was bullocks having used an incorrect date.
My Garmin GPSMap 750 went back to Jan 2002 last summer. After speaking to Garmin support I installed a firmware update and we are now back in 2022.
 

Boathook

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My furunoGP-31 gave the wrong date after the last rollover. The time is correct along with the position so I carry on using it to give data to the dsc radio. I could use the plotter but that isn't always on so the furuno carries on until the position gets wrong.

Edit. Just looked at the list of effected models and mine isn't on it. Hopefully it will just carry on with incorrect date ......
 

andsarkit

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My furunoGP-31 gave the wrong date after the last rollover. The time is correct along with the position so I carry on using it to give data to the dsc radio. I could use the plotter but that isn't always on so the furuno carries on until the position gets wrong.

Edit. Just looked at the list of effected models and mine isn't on it. Hopefully it will just carry on with incorrect date ......
If you scroll down the GP31 is on the 2019 failure list. My GP31 has an incorrect date but also has a small error in position. I think it is a couple of hundred metres but I need to monitor it to see if it is constant. Furuno advice is to buy another unit which is a shame as it is a nice simple robust GPS. Furuno obviously knew this was a predictable problem but were happy to sell the units without informing buyers that they wouId fail in 20 years. I have a Garmin and Magellan handhelds that are very old but still coped with the rollover.
Suggest you check your unit against another GPS or even a phone.
 

westhinder

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Thanks for the heads-up, I have GP32 on the boat so I'd best check that out.
My GP 32 has given the wrong date since the 2021 rollover. The position looks to be roughly correct.
I’m not overly worried by it as it is a standalone unit at the chart table. I have a plotter, a vhf and an AIS which each have their own gps sources, plus an iPad and a number of smartphones on board.
 

RobbieW

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My GP 32 has given the wrong date since the 2021 rollover. The position looks to be roughly correct.
I’m not overly worried by it as it is a standalone unit at the chart table. I have a plotter, a vhf and an AIS which each have their own gps sources, plus an iPad and a number of smartphones on board.
Thanks, didn't use the boat last year. The GP32 feeds both AIS rx and VHF
 

robmcg

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I had a GP30 that succumbed to the rollover issue a few years back. I can confirm the position was always correct though ?. Unrelated but the sat Nov in my Honda has just succumbed to the same rollover issue - position is still accurate but every time you start the car the time is always 15.01 ?
 

TSB240

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Just checked my new to me boat. The secondary Furuno GP30 at the chart table thinks it is June 2002. The time is right and the position is the same as my phone. It is currently providing the DSC radio with position.
 

Porthandbuoy

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Shows Furuno had a lack of confidence in their kit lasting 19 years. Shoddy design when you consider the date is available from the GPS satellites.
I wrote to them asking if a firmware upgrade could be designed that would allow users to add mm/did/yy, or even n000’s of hours to the time akin to the local time offset from GMT.
The answer was “Sorry, no. It would require re-writing to flash eproms”
Would be great project for some electronic geek.

I have the GP-32 Navigator in the wheelhouse and the Navtex, as a repeater, in the saloon. Position is good, date is wrong.
 
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st599

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If you scroll down the GP31 is on the 2019 failure list. My GP31 has an incorrect date but also has a small error in position. I think it is a couple of hundred metres but I need to monitor it to see if it is constant. Furuno advice is to buy another unit which is a shame as it is a nice simple robust GPS. Furuno obviously knew this was a predictable problem but were happy to sell the units without informing buyers that they wouId fail in 20 years. I have a Garmin and Magellan handhelds that are very old but still coped with the rollover.
Suggest you check your unit against another GPS or even a phone.

If the GPS unit is storing the wrong date and time, how does it know if the almanac from the GPS satellite is current?
 

mjcoon

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If the GPS unit is storing the wrong date and time, how does it know if the almanac from the GPS satellite is current?
It's equivalent to omitting the century from the year. If you assume you are both working in the current century you get the right answer. But of course in this case the rollover period is much shorter than 100 years!
 

justanothersailboat

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I noticed my boat's old Garmin GPS' clock was an hour out, on my last sail of December. My old hiking GPS takes up a large error of position on a regular, scheduled basis, say every other half hour or something, then gets it right again for the same duration, and repeat. My phone sometimes goes from near-as-damnit live to a lag of several minutes, which is not terribly helpful with Navionics sometimes. From this I conclude that I really had better treat ALL gps as a pleasant, useful tool that I should be prepared to question or disregard at any time and always need to have an internal mental picture that can check it and pick up the slack. Or stop being a cheapskate and buy some new toys... but I work in software (more or less) so I just can't get excited about the prospect.

In their defence, both dedicated GPSes are so old that their developers probably had to fit everything into tiny microcontrollers. The boat's set is so old it may first have been used to locate Mount Ararat.

Or maybe I'm just cursed and GPS only does this for me, not everybody else :)

All I ask is a small ship and a synthetic star to steer her by...
 

Stemar

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I probably know just enough about programming to be dangerous, but 2^10 seems like an odd sort of number unless they were using 5 bits, which, again seems odd.

I'm to old to faff around with an astrolabe, so

All I ask is a small chip and a satellite to steer her by...
 

mjcoon

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I probably know just enough about programming to be dangerous, but 2^10 seems like an odd sort of number unless they were using 5 bits, which, again seems odd.

I'm to old to faff around with an astrolabe, so

All I ask is a small chip and a satellite to steer her by...
Surprise, surprise, but 2^10 takes 10 bits. Perhaps you were thinking of two rows of 5-hole paper tape? ;-)

Four satellites are more useful for steering, or maybe three if certain to be at sea level... That counts as a constellation, so long as you don't expect them to be reminiscent of a bear, or dipper, or anything!
 

justanothersailboat

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I don't know Stemar... seems to me that in old stuff where they used tiny microcontrollers with ram and storage of a few kilobytes because that was what you could get for a low-power portable device at the time, bit-packing type techniques where you cram a couple of status bits and a couple of bits of data into a single byte are quite common (trading a bit more code for much more efficient use of storage) so I wouldn't be entirely surprised.

And I wouldn't even be that surprised if a similar limitation made it onto a more modern device with a bigger chip if it was lurking somewhere in underlying code that was reused. I don't work in embedded device stuff like this but I've occasionally seen modern software formats still replicate the shape of long-ago bit-packings inside them due to quirks of how they evolved. I think I've seen just a bit too much of the software sausage being made...
 
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