Converting instruments to MPH

Discussion in 'Gen 2 Prius Accessories & Modifications' started by EtN, Jun 5, 2008.

  1. EtN

    EtN Irish-Italian Hybrid

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    Hello all,
    I have a nice green Prius which I bought in Ireland, where I lived before moving to the UK where I'm now.
    The problem is that, unlike American models that sport a nice button that allows you to switch the speedo from MPH to KMH, my car has a useless dimmer in the same spot and everything is fixed in KMH. Since UK registration procedures demand that the speedo HAS to display MPH *and* KMH (together or via a toggle switch), my car is currently not fit to be registered in the UK for this tiny detail alone.
    What can I do to solve this problem? Should I buy a replacement monitor/head unit and the associated electronics (incl. the much wanted kmh/mph button) will it work? Any input greatly appreciated, I don't want to sell the prius :p

    I was thinking about something along those lines:
    eBay Motors: 2004 2005 2006 2007 Prius Non-Navigation Display Screen (item 230258449930 end time Jul-02-08 07:56:57 PDT)

    Thanks
    Tony
     
  2. SureValla

    SureValla Member

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    can you post a picture of the dimmer switch in the kph/mph button switch?

    dimmer is on the left switch button is on the right next to the flasher button
     
  3. EtN

    EtN Irish-Italian Hybrid

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    I don't have a camera with me but I can tell you that the last button to the right in my onboard computer is the dimmer and not KMH/MPH like in the US models. My screen is like the Australian version. In this image http://www.rits.net.au/prius/Images/PB306304.JPG you can see my same layout of buttons: 1986-era LCD clock, hazard lights, odo/trip switch and dimmer.

    Tony
     
  4. hiremichaelreid

    hiremichaelreid New Member

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    Canadian model has the KMH / MPH switch also.

    I would bet 10:1 that a switch could be added to any Prius without the switch. IMO you probably just need someone to find where to add it (wirewise) and to add one.

    But I'm not 100% sure, so don't take my bet as gospel.
     
  5. EtN

    EtN Irish-Italian Hybrid

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    I'm pretty sure the smarts are there (in the head unit computer) as it's quite trivial an operation for such a sophisticated computer as the prius' to convert KMH to MPH at the end of the day but while I might be able to replace the whole enchilada, finding a way to locate the switch looks like a nontrivial task to me. I wonder if all the computer does is acting like a glorified scangauge and picking up signals from the CAN bus (feeding the speedo) but it looks that way to me.

    Thanks
    Tony
     
  6. b11101100

    b11101100 Spectra Blue Mica Driver

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    ScanGauge II

    I haven't ever used one of these yet, but it looks like they can display vehicle speed in MPH. Look in the PC shop for the scan gauge II. Lots of people use these here. Hopefully one of them will chime in and let you know if it's suitable for us as a speedometer when properly mounted.

    If there is someway to provide support for the KPH/MPH switch that would be a better solution, but I wanted to throw this out there for consideration.
     
  7. SureValla

    SureValla Member

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    I wish the km/h to mph button was more of a US to metric button like in my dodge caravan. It converts all the measurements to metric (temp, odometer, etc)
     
  8. hiremichaelreid

    hiremichaelreid New Member

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    Yes, I'd like more control over iMPG units. Perhaps the switch is intended for those who travel in countries with both metric and imperial speed limits, like for those who travel in both US and Canada. It's easier to keep to the local speed units rather than mentally calculating each new speed limit sign.

    I guess speedometer and odometer unit requirements are set by law, but the IMPG units are not.

    I started driving in Canada in 1979 and STILL think in terms of Imperial MPG. My 1975 Bobcat and 1979 Pinto got about 30 Imperial MPG or about 25 US MPG. Guess that's about 9L/100KM. Pinto is my longstanding benchmark.
     
  9. Batavier

    Batavier Member

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    I'm also interested in a solution to this problem. I often go on holidays in the UK (with my Prius :) ) and it would certainly be nice to be able to switch from KM/h to MPH. My TomTom can display the speeds, but I just want the Prius to who MPH as well. :)
     
  10. SureValla

    SureValla Member

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    im interested b/c i think it would be interesting to become accustomed to metric units (a far superior system IMO) and what they mean in real life
     
  11. biggus

    biggus Junior Member

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    2004 Irish Prius has facility to switch from MPH to Kmh have a look at an older uk model at a dealer to see if its switchable and see if the wiring is the same as yours. if so borrow the button to switch over. Any way Toyota diagnostics machine can probaly reset to MPH anyway.
     
  12. EtN

    EtN Irish-Italian Hybrid

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    I had a chat with my local Toyota dealer and they said they don't know how to solve this problem. The 2004 has the switch as the metric switchover (in Ireland) happened in the first months of 2005. I wonder what part number that unit is. I wrote to their HQ in the UK to see if they can help me, otherwise I'll buy the part on ebay and try :p. BTW, the UK version of the Prius still has the switch to date. Confusing huh?
     
  13. EtN

    EtN Irish-Italian Hybrid

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    Hello all,
    I've decided (after having heard nothing from Toyota) to go ahead and try and fit a US button set to my current car. I've sourced the part from a supplier found in a previous PC discussion and my firm intention is to compare the wiring of the two button sets to see where the heck does the kmh/mph switch tap its juice from (relocating the dimmer switch to somewhere else would be a nice plus but secondary to my purpose ;). I'll keep you posted and, just in case, I'll document everything with photos :)

    Tony
     
  14. SureValla

    SureValla Member

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    nice, im interested to see how that goes
     
  15. EtN

    EtN Irish-Italian Hybrid

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    Hello all,

    I have to report that, unfortunately, changing the buttons doesn't change the car's behaviour. I kinda expected that actually, given the fact that the buttons themselves don't have any "smarts" but only the captions are different. I'd say the electronics might be there but without the specs (techinfo is strictly us-only and I need the schematics for my specific model) I'm forced to beg Toyota to find me a solution. Meh.

    Tony

    P.s.: If you need a used part for your Prius in the US I recommend Steve of AutoBeYours who has been very helpful in sourcing the needed button set in record time. I'm of course just a customer with no affiliation (I have received a free AutoBeYours pen so I might be a little biased, LOL) so YMMV.
     
  16. The Tramp

    The Tramp Italian Prius Expert

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    [​IMG]
     
  17. The Tramp

    The Tramp Italian Prius Expert

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    What a Bummer!
    I thought that the Irish prius would have had a MPH/KPH switch since they recently changed and anywhere you go you are in the UK!
     
  18. EtN

    EtN Irish-Italian Hybrid

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    Ciao Tramp (I was born in Turin! eh!),

    Ireland (as in the Repulblic of Ireland) is not in the UK but Northern Ireland is, so it would have been nice of Toyota if they provided us with the KMH/MPH button for our trips up North. The Irish version is the same as the Australian version, I think it costs less for Toyota not to cater for the Irish market with a model that defaults to Km/h and can switch to MPH via a switch. I love the Prius but I'm very dissatisfied. What's more, Toyota UK didn't reply to my fax where I asked for help (at a premium, of course), I'll try with the Irish counterpart, what more can I do.

    The UK model defaults to MPH and the switch can be used for BOTH kmh/mph AND dimmer, so it surely CAN be done but nobody (Yes, Toyota, I'm looking at you) seem to care about the fact that a 30 grand car is let down by a (beep)ing missing switch.

    Tony
     
  19. The Tramp

    The Tramp Italian Prius Expert

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    Ciao EtN (I was born in London) :-P

    I know the situation since I lived in Dublin, my wife is from belfast and we often go up (by Prius) From Turin to Belfast Via Stena's Holyhead-Dun Laoghaire fast ferry.

    Back on topic, I'm afraid that you may have to change the whole (beep)ing MFD, for one single missing switch.

    It would be easier to sell the Irish prius in Ireland and buy a UK Prius in the UK.
     
  20. EtN

    EtN Irish-Italian Hybrid

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    Tramp,

    Changing the MFD won't solve the problem either. The switch bank located below the MFD doesn't feed from the MFD itself but taps directly into the cars' electronics via a wire harness. From the technical documentation I've got, the KMH/MPH switch should get its signal from the "AVC LAN". Is there a way to interface this?

    I thought about selling but, apart from the depreciation issue, there are other financial worries as the car is under a finance agreement so, in brief, it can't be sold if not by a special permission by the finance company and paying a hefty premium.

    I was in Turin (and continued all the way into the area my other relatives are, Puglia) with the Irish Prius last May, lived in Dublin (Blanchardstown), had a girlfriend from Belfast at one stage and came back from Puglia to the UK, the car loaded with booze like a Transit van, 5500 Kilometers round-trip without the Prius skipping a beat. Even if we don't consider the green features and the free road tax, the Prius still is an amazing piece of engineering.
     
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