MPH - KPH conversion

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Fri 24 Jun 2005 10:11
MPH - KPH conversion - AR-CoolC
I don't know why, but it occure to me this morning that whilst my car has a inner ring on the speedo showing my speed in KPH, when I have driven hire cars aroard there has not been the equvilent MPH inner ring.

Is there a specific reason why UK cars have this conversion scale?

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Fri 24 Jun 2005 11:19
MPH - KPH conversion - dilbert
This occurred to me, too, when I saw the speedo in a French colleague's Chrysler - it has a main km/h scale and an inner MPH scale. It's the only car I've seen like this.

I figured that UK-market cars have the inner km/h scale as part of type approval (the standards by which cars are designed) in preparation for the seemingly unlikely event that we convert to metric road signs. Or maybe it is just in recognition of the fact that if you leave the UK and travel by car to any other country on planet Earth (except the USA) you will need the km/h scale....

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Fri 24 Jun 2005 11:32
MPH - KPH conversion - Altea Ego
to follow on, do all UK cars with digital speedos have a hidden "kmh" function?
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Fri 24 Jun 2005 12:18
MPH - KPH conversion - blue_haddock
I don't know about all cars with a digital speedo but the Toyota Yaris and Prius can easily be switched between MPH and KPH
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Fri 24 Jun 2005 13:29
MPH - KPH conversion - Rebecca {P}
A BMW 3 series can show either, as can a Citroen Picasso.
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Fri 24 Jun 2005 13:55
MPH - KPH conversion - SjB {P}
On any pre-facelift Vectra (i.e up to year 2000 model year) the odometer and trip counter can be toggled between miles and kilometres by pressing and holding the reset button whilst turning the 'ignition' switch on.

I don't know why, but when the instrument cluster was subtly redesigned for 2000 (part of which redesign was to relocate the trip odometer and trip counter to prevent obscuration by the steering column cowl) this nice feature was dropped.
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Fri 24 Jun 2005 14:47
MPH - KPH conversion - Dynamic Dave
On any pre-facelift Vectra (i.e up to year 2000 model year)
the odometer and trip counter can be toggled between miles and
kilometres by pressing and holding the reset button whilst turning the
'ignition' switch on.


I thought all that did was to get rid of the INSP message?
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Fri 24 Jun 2005 15:15
MPH - KPH conversion - Dwight Van Driver
Current UK Law that speedometer on modern cars have to indicate speed in both mph and kph.

DVD
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Fri 24 Jun 2005 19:04
MPH - KPH conversion - martint123
DVD said:- Current UK Law that speedometer on modern cars have to indicate speed in both mph and kph.

Should that read "be capable of" rather than "have to". My speedo can show one or the other but not "both".

Martin
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Fri 24 Jun 2005 15:38
MPH - KPH conversion - SjB {P}
I thought all that did was to get rid of the
INSP message?


Not according to the source that told me, and the actual practice borne out through either trying out of interest or using out of benefit when abroad; I have used this technique on my 1998 SRi V6 Estate, brother's 1999 1.8 LS Estate, and numerous Vectra hire cars during that period.

I was also told that the feature was discontinued with 2000 models, and sure enough, on my 2000 GSi Estate and brother's 2000 1.8 Estate, it was.
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Fri 24 Jun 2005 19:51
MPH - KPH conversion - Dynamic Dave
>> I thought all that did was to get rid of the INSP message?
>>
Not according to the source that told me,


How long do you have to hold the trip reset in for for the conversion?
To reset the INSP you have to hold it in for several seconds.
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Wed 22 Apr 2009 23:50
MPH - KPH conversion - diddy1234
I thought that as well.

After My Astra had a main service the INSP light was still on.
So I took it back to Vauxhall's and that's how they turned the INSP light off
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Wed 22 Apr 2009 23:50
MPH - KPH conversion - scouseford
INSP ?
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Wed 22 Apr 2009 23:55
MPH - KPH conversion - diddy1234
INSP = inspection due /service needed.

Its just a mileage counter that should get reset by a technician after a service.
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Thu 23 Apr 2009 10:34
MPH - KPH conversion - OldSock
My 1989 Jaguar XJ40 could display speed in km/hr via the VFD display (speedo marked only in mph).
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Wed 22 Apr 2009 23:40
MPH - KPH conversion - shakennstirred
I don't know about all cars with a digital speedo but the Toyota Yaris and
Prius can easily be switched between MPH and KPH

how do you do it?
i have a yaris loan car and the digi speedo is set to kph
thanks
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Thu 23 Apr 2009 00:02
MPH - KPH conversion - 1400ted
I've suffered on two counts here, both with motorbikes. A Swiss Condor I bought and only used in GB had a KPH only speedo and a BMW R45 that I used here and went all over Europe on had MPH only .

You quickly got used to doing all the mental arithmetic whilst on the move !
Ted
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Thu 23 Apr 2009 00:05
MPH - KPH conversion - madux
You can't buy a tape measure with inches on it on the Continent.
In the US you can, of course, or you could buy a metric one, but you can't buy one with both inches and centimetres on.
We have the best of both worlds here.
Very useful when cutting a bit of wood to be able to choose between, say, a sawcut more than 1cm and a sawcut less than 28" !
Makes you proud to be British :)
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Thu 23 Apr 2009 01:16
MPH - KPH conversion - Bilboman
"Best of both worlds" - worst of both worlds, more like. Has anyone ever sat down and worked out the cost of this half-baked half-metric folly?
Can any rational human being explain why in 1971 we went fully decimal but only made a vague nod in the direction of metrication and 40-odd years later are still in a halfway house?
Is there perhaps any perverse conection to the fact that while the whole world is learning and speaking our language, in Britain we just can't be bothered to "speak metric"?
Most HGVs have tachographs (and speeding fines??) measured in kph only. Inches are used to measure TV screens all over the EU except in Britain, where we, erm, "converted" to cms. And as for tyre sizes...(had an awful job trying to get hold of TD tyres for my Montego in Spain...)
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Thu 23 Apr 2009 07:26
MPH - KPH conversion - L'escargot
Is there a specific reason why UK cars have this conversion scale?


Perhaps not, but I like it because it adds a bit of interest to what is basically a somewhat boring instrument. On the other hand it could be of assistance if you ever take your car abroad.

Edited by L'escargot on 23/04/2009 at 07:27

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Thu 23 Apr 2009 09:09
MPH - KPH conversion - jc2
The only LEGAL requirement in the EU is for KPH to be shown.About 90% of cars sold in the EU are for KPH markets.Cars sold in the UK have MPH as well which is not required elsewhere in the EU.
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Thu 23 Apr 2009 10:28
MPH - KPH conversion - Falkirk Bairn
We will go fully metric after the USA has ................i.e. Never!
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Thu 23 Apr 2009 15:26
MPH - KPH conversion - mufcnumber18
My 2007 Volvo S80 only has mph on the speedo. There is a function within the trip display (i.e shows mpg, av speed etc) that also can be used to show current speed in kmh, but you have to select this function and whilst using it cannot therefore see the other trip computer functions.

Seems sensible for UK cars to show mph (and the volvo does so very clearly as it hasn't been cluttered with a load of red numbers in the middle of the speedo), but with the ability to display kmh for trips abroad.


Posting, as always, in the hope that it helps.
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Thu 23 Apr 2009 19:52
MPH - KPH conversion - mike hannon
When I asked Bentley direct about exporting a 1990s car they came back, very politely and helpfully, and said 'we will only issue the relevant paperwork if you have modifications done by an official Bentley dealer and you will need a new speedometer, reading in KPH. That will be 800 pounds odd plus VAT'.
When I rang and pointed out that the cars already have speedometers that read clearly in miles and kilometres, the very helpful young woman said 'oh, all right then...''
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