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Hi all, I had my 2019 Kona 1st service last month. Apparently it had a "recall software update" not sure what for.
But more importantly for me the annual map and satnav update. The nav system seems much improved with more adjustable items and improved graphics, although to be fair I had no complaints before.
However one thing I have noticed is the on-map speed display is consistently reading low. Between 60 and 70 mph it reads 4mph low compared with the speedometer and cruise control readouts which agree with each other.
Has any one else noticed this.
 

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I am still waiting for my maps update (I was still on original 2018 versions for everything) as when the dealer tried to do the updates it failed so badly that a new unit is required, The most annoying aspect is temporarily not having the HUD. its a £4k warranty repair!

Booked in for next Friday so lets see how it all works after that.
 

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It's utterly surprising that with car models with both GPS and a CAN bus based dash, that the GPS speed isn't used to calibrate over time the wheel-rotation based speedometer and odometer - which does vary in accuracy depending on air pressure, tyre pressure and tyre wear. The GPS measurements are going to be more accurate, providing it can get a reliable signal, and the wheel rotation is going to be more accurate in tunnels.
 

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It's utterly surprising that with car models with both GPS and a CAN bus based dash, that the GPS speed isn't used to calibrate over time the wheel-rotation based speedometer and odometer - which does vary in accuracy depending on air pressure, tyre pressure and tyre wear. The GPS measurements are going to be more accurate, providing it can get a reliable signal, and the wheel rotation is going to be more accurate in tunnels.
While GPS speed should be fairly accurate it still has error bars, and can jump about if the signal is flaky.

By law speedometer are not allowed to under-read ... at all. So they are deliberately calibrated to over-read a little. No manufacturer is going to sail close enough to the law to risk a slightly off car giving them a legal headache and potential recalls.

I expect the apparent change of that nav display speed from GPS back to car is part of that thinking - or simply just that dealers are fed up with customers coming in and complaining that the numbers are different.

Modem cars with electronic units seem to be a bit nearer real speed than the mechanical ones or old, with 3-4 mph over-read being typical. I recall 5-6 mph being common at motorway speeds in the past.
 

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Hi all, I had my 2019 Kona 1st service last month. Apparently it had a "recall software update" not sure what for.
But more importantly for me the annual map and satnav update. The nav system seems much improved with more adjustable items and improved graphics, although to be fair I had no complaints before.
However one thing I have noticed is the on-map speed display is consistently reading low. Between 60 and 70 mph it reads 4mph low compared with the speedometer and cruise control readouts which agree with each other.
Has any one else noticed this.
I expect the ‘recall software update’ may have been the BMS update which changes some things in the Battery Management System. Have you still got the aux battery + option in your menu? Have you tried to charge on a 150kwh Rapid charger since it was done?
 

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Our Kona reads 65mph at GPS 60mph, and 75-76mph at GPS 70mph, and the Zoe is about the same as was the Ampera before that. 8% is typical on most cars it seems, though some seem to work on "GPS speed plus a bit".
 

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Our Kona reads 65mph at GPS 60mph, and 75-76mph at GPS 70mph, and the Zoe is about the same as was the Ampera before that. 8% is typical on most cars it seems, though some seem to work on "GPS speed plus a bit".
Our Kona is consistently 3, occasionally 4, mph difference at anything from 30-70 mph. My previous modern car was similar.
About 7-8% across the range was typical on older ones which I attributed to being calibrated near the middle of the legal limits which were/are (a little more complex but) roughly +0 to -15%.
(I did a lot of motorway miles back then, so getting a few extra mph legal speed made a difference.)
 
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