Any - Speedometer dial calibration

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Fri 8 Mar 2013 18:00
Any - Speedometer dial calibration - nick62

Just got a new car and the speedometer dial is ONLY calibrated in MPH.

I cannot remember being in any UK car less than 40 years old that did not have secondary KPH calibration inside the MPH markings as well.

I thought this was a requirement in UK cars, is this an urban myth or has legislation changed recently?

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Fri 8 Mar 2013 18:17
Any - Speedometer dial calibration - Hamsafar

Cand you conjure up a kph display via some menu?

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Fri 8 Mar 2013 18:21
Any - Speedometer dial calibration - nick62

Cand you conjure up a kph display via some menu?

No, I have tried and there is no possibility to do this!

Remarkable how "uncluttered" the speedo appears with just one set of numbers.

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Fri 8 Mar 2013 18:31
Any - Speedometer dial calibration - Collos25

What type of car is it ?

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Fri 8 Mar 2013 18:32
Any - Speedometer dial calibration - nick62

Range Rover Evoque (SWMBO)

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Fri 8 Mar 2013 18:34
Any - Speedometer dial calibration - RT

If there is a legal requirement, it'll be MPH for the UK - we are still an imperial measurement country despite efforts to metricate everything.

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Fri 8 Mar 2013 18:39
Any - Speedometer dial calibration - nick62

I thought it must be a UK requirement to have KPH as well as the normal MPH markings in the UK, (why else would manufacturers do this since god knows when, certainly not out of the goodness of their hearts)?

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Fri 8 Mar 2013 18:41
Any - Speedometer dial calibration - Collos25

We have actually been a metric country since legislation in 1972 but a special dispensation allows us to sell beer and milk in pint glasses and containers and have distances in miles.The mentioned car if it was bought in the EU should have a provision to change the MPH to KMH or have dual readings, if its been sourced in a non EU country for a non EU market then not.

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Fri 8 Mar 2013 18:46
Any - Speedometer dial calibration - elekie&a/c doctor

There is no legal requirement to provide a speed indication in kph.A speedo is not even part of an mot test.Many european left drive cars only have their speedo calibration in kph only,unless there is a digital display available on instrument menu .Could be time to find your Dymo label maker??

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Fri 8 Mar 2013 19:01
Any - Speedometer dial calibration - Cyd

Sorry, but this is wrong. It has nothing whatsoever to do with the MoT.

All cars sold across Europe must meet ECE homologation requirements, which requires speed to be scaled in Km/h. However a dispensation in the legislation allows the Km scale to be a secondary one against the miles on a UK market car.

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Fri 8 Mar 2013 18:52
Any - Speedometer dial calibration - Cyd

It is my understanding that it is a homologation (ie legal) requirement for UK speedos to have secondary Km markings. However there is no such requirement for US speedos. It would be my theory that your car has somehow been fitted with a US speedo in error. Fortunately US miles are the same as UK miles (unlike pints and gallons).

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Fri 8 Mar 2013 18:57
Any - Speedometer dial calibration - Collos25

Correct.

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Fri 8 Mar 2013 19:03
Any - Speedometer dial calibration - Cyd

Strictly speaking the car is illegal for the whole of the European market (incl the UK). I have no idea what the consequences might be should you be stopped for speeding on the continent.

Take it up with the dealer and request (demand) a UK speedo is fitted.

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Fri 8 Mar 2013 19:12
Any - Speedometer dial calibration - Collos25

In EU land not having a speedo which read KMs would entail the car being taken of the road until one was fitted.

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Fri 8 Mar 2013 19:12
Any - Speedometer dial calibration - RT

Strictly speaking the car is illegal for the whole of the European market (incl the UK). I have no idea what the consequences might be should you be stopped for speeding on the continent.

Take it up with the dealer and request (demand) a UK speedo is fitted.

Probably needs more than just a speedo - if it is US a production part then the trip computer will be calibrated wrongly as well.

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Fri 8 Mar 2013 19:14
Any - Speedometer dial calibration - Collos25

Why its only the speedometer, trip and total mileage are irrelevant as far as regulations are concerned

Edited by Collos25 on 08/03/2013 at 19:15

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Fri 8 Mar 2013 19:22
Any - Speedometer dial calibration - Collos25

If its not a USA model part thats slipped the net then you can change it at will its a TFT display and you can have all measurements either metric or imperial.I gleemed that info from the LR site on the internet the OP has the manual I am sure the instructions for changing are in there if he cares to read them.

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Fri 8 Mar 2013 19:24
Any - Speedometer dial calibration - RT

Why its only the speedometer, trip and total mileage are irrelevant as far as regulations are concerned

In terms of legalities, that's correct - but a mis-calibrated trip computer still needs correcting.

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Fri 8 Mar 2013 19:44
Any - Speedometer dial calibration - Collos25

Why would it miscalibrated an American mile is the same as a UK mile or am I missing something.

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Fri 8 Mar 2013 19:50
Any - Speedometer dial calibration - RT

Why would it miscalibrated an American mile is the same as a UK mile or am I missing something.

The miles are the same but the gallons aren't - so MPG will be wrong.

US gallon is significantly smaller than Imperial gallon - one of the reasons US cars appear to have much worse consumption than ours.

Edited by RT on 08/03/2013 at 19:51

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Fri 8 Mar 2013 19:19
Any - Speedometer dial calibration - Cyd

That will depend on where the TC processing is carried out. It is likely the instrument cluster is simply a remote display unit and the processing is carried out elsewhere in another ECU.

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Fri 8 Mar 2013 19:52
Any - Speedometer dial calibration - focussed

A US gallon is very different to an imperial (UK) gallon, hence the trip computer readout will be way out.

UK gallon = 4.54 litres

US gallon = 3.78 litres

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Fri 8 Mar 2013 20:01
Any - Speedometer dial calibration - Collos25

I see what your getting at the average readout will be wrong if you want to work out mpg ,I was refering only to the distance readout.The chances are the OP has not read the manual.

Edited by Collos25 on 08/03/2013 at 20:02

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Fri 8 Mar 2013 20:09
Any - Speedometer dial calibration - Galaxy

Time to get busy with the felt-tip marker, methinks.

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Sat 9 Mar 2013 18:35
Any - Speedometer dial calibration - Avant

I would imagine that a sawn-off Range Rover is upmarket enough to have some form of trip computer. There will surely be some setting that allows kph to be displayed on the computer screen, even if not the speedometer.

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Sat 9 Mar 2013 19:06
Any - Speedometer dial calibration - Collos25

There is the OP has not read the manual stated a few post back.

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Sat 9 Mar 2013 20:46
Any - Speedometer dial calibration - nick62

OK, problem solved..............resorted to RTFM (again), but still no joy!

Sat and twiddled several settings on varoius screens and just as I nearly gave-up the will to live, I "found" the right menu.

As other have suggested, there is the possibility to display the speed digitally on a small central display, this can be changed to KPH.

Edited by nick62 on 09/03/2013 at 20:48

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Wed 13 Mar 2013 21:54
Any - Speedometer dial calibration - Smileyman

Putting aside the issues of legality etc I cannot see a problem with miles only display. It's not that hard to follow speed limits in KM, after a few minutes with a conversion chart it will seem like second nature.

However I do see a problem with changing the speedo if the odometer is part of this - there are always going to be questions about the exact mileage of the vehicle, and it's always better to avoid creating a question requiring an answer and having to explain why...

I remember my Austin Maestro car had two new odometers, both repalced under warranty. (enough said)

More of a problem is when the wheel size is changed, as the speedo will read incorrectly.

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Wed 13 Mar 2013 22:00
Any - Speedometer dial calibration - Avant

"More of a problem is when the wheel size is changed, as the speedo will read incorrectly."

More views on that point woulds be interesting. My Octavia is on winter tyres (205/55/16)and 16" steel wheels, compared with the original 225/40/18 setup. Over a known journey the odometer read the same - I have assumed because the overall diameter of wheel + tyre is much the same.

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Thu 14 Mar 2013 07:23
Any - Speedometer dial calibration - RT

It's normal for different wheel/tyre options to be available - but all giving the same rolling radius and thus keeping the gearing the same.

My SUV can have 235/70x16, 235/65x17, 235/60x18 or 235/55x19 - which are all the same radius/gear, for all practical purposes.

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Thu 14 Mar 2013 09:05
Any - Speedometer dial calibration - NARU

I remember hiring a car in New York state, which had an apparently 'miles only' speedo, but pressing a button turned it to Km (for use in Canada).

Pressing the button made the needle jump from (say) 50 on the display to 80. And a little 'km' light to come up in the centre to replace the mph light.

Worked very well, and much better than the way we do it over here.

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Thu 14 Mar 2013 10:31
Any - Speedometer dial calibration - RT

The Vauxhall Senator with the digital dash could do that - I took great delight in frightening my passengers on a high speed run by suddenly switching from 127 mph to 204 kph without telling them !!

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Thu 14 Mar 2013 07:54
Any - Speedometer dial calibration - TeeCee

"More of a problem is when the wheel size is changed, as the speedo will read incorrectly."

Yes, but speedos intentionally overread and by more than enough to handle a slight difference in rolling diameter.

If you fire up the diagnostic menu on a Prius, one of the things you can get displayed is the speed as returned by the vehicle speed sensor. It's quite interesting to see the difference between that and the speed shown in big numbers on the dash display. There's quite obviously a fiddle factor being added on between the one and the other to cover the manufacturer's backside.

On an analogue clock driven by a cable you could put any discrepancy down to calibration, but this shows that they do it quite deliberately.

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