[anj48]

My speedometer is reading much higher than my actual speed, if I am going say around 50 mph it will read maybe 90 or so, this happens over the entire range of speeds. It has been going on for about the last fifty miles of driving which has included several stops and starts so it is not a matter of "rebooting". Otherwise the car seems to be operating normally so I am guessing that the problem lies with some sensor or device that reads the RPM of the wheels (the odometer is reading properly however).

The car has 9500 miles on it so I will be taking it in soon for the 10,000 mile maintenance - plan to have it checked then. I searched the forum on "speedometer" but didn't find that anyone else has had this problem. Any comments or advice would be appreciated.

 

[wstander]

Check the mph/kph button on the dash near the ODO reset and emergency flashers button.

Perhaps you inadvertantly tapped it into the KPH mode the last time you reset the trip ododmeter...

 

[MikeFromEastCoast]

Maybe you're in kph mode? I think you hit the trip button to switch between.

 

[mrv]

62/63 MPH = 100 kph.

Yes, check the toggle button for MPH/kph.

 

[wstander]

In review, would not the KPH/MPH button also change the odometer to km from miles though?

The OP noted (and I quick triggered my first response) that they were at 9500 miles and coming up on the 10000 mile service.

If the odometer is showing miles but the speedometer is showing KPH, that is wrong and something is not switching or converting to the display.

Curiouser and curiouser....

 

[fish_antlers]

I'm not sure about the Prius, but with regards to motorcycles almost all brand new bikes read +/- 3 to 8% out. Several companines make products to correct speedo error for motorcycles, the two largest are the yellowbox and the speedohealer.

I can only assume there are similar products for automobiles, probably can be found if you googe either of those companies.

BTW if you over and or underinflate your tires this will alos further affect your speedo reading as it changes the circumference of your tires.

You can try taking a GPS with you to get an accurate reading of your true speed and to accurateloy measure what percentage you are out.

 

[Seven7]

In review, would not the KPH/MPH button also change the odometer to km from miles though?

The OP noted (and I quick triggered my first response) that they were at 9500 miles and coming up on the 10000 mile service.

If the odometer is showing miles but the speedometer is showing KPH, that is wrong and something is not switching or converting to the display.

Curiouser and curiouser....

I believe the KMH/MPH button only switches the speed display, to help out foreign drivers or while you are foreign driving, and not the mileage from miles to kilometers... or temperature from ferienheit to celcius... or the steering wheel to the other side of the car.

 

[anj48]

Duuuuhhh!

Duuh! Of course that was the problem, I had pressed the KPH button. And stared right at it on the display without any neurons firing.

Thank you for responding. I'm sure glad nothing is wrong.

 

[wstander]

Which, now that I went to the car and checked, brings up the question as to why the odometer does NOT shift to kilometers when the kph button is engaged.

Just strikes me as odd that the speedometer can be shifted but not the odometer.

Is there a technician only switch buried in the entrails that places the odometer in to kilometers? If I recall correctly, Canada and Mexico still use the English miles system, but how about South America?

Walt

 

[rpm]

Re: Duuuuhhh!

Duuh! Of course that was the problem, I had pressed the KPH button. And stared right at it on the display without any neurons firing.

don't feel bad, I've done the same (twice)!
rpm

 

[DanMan32]

If I recall correctly, Canada and Mexico still use the English miles system, but how about South America?

Walt

Canada doesn't, or at least I can vouche for the province of Quebec. Only metric there.

 

[mrv]

In review, would not the KPH/MPH button also change the odometer to km from miles though?

The MPH/kph toggle button only changes the spedometer. It does not change the odometer or the trip odometers. Nor does it change the MFD to read in l/100km as listed on Canadian Prius as opposed to MPG, nor does it change the temperature to C from F.

BTW: Canadian Prius' odometers are in kilometers, not miles.

 

[mrv]

Re: Duuuuhhh!

Duuh! Of course that was the problem, I had pressed the KPH button. And stared right at it on the display without any neurons firing.

don't feel bad, I've done the same (twice)!

Yeah, been there too.

Even scarier is accidentially turning the interior light dimmer wheel switch all the way down and not realizing it. Go to look at the spedometer or the odometer, and there's nothing displayed there at all (just black)! Eek, did the display just die?!? Find the wheel, all is calm again.

 

[iggy1iggy]

My wife had the same thing happen to her and she called me up while she was driving down a country road saying "I am going 55 but it seams like I am standing still, what is wrong?!" I told her what button to push and it fixed the prob. But later she called me back and said it happened again! and I figured out that my security badge was hanging on it's lanyard from the rearview mirror swung and hit the button.

 

[DanMan32]

I think I remember you posting your wife's phenomenon. That was funny.

So, if you want to impress or freak out somebody, set it to KpH when driving.

 

[wstander]

[quote="mrv
BTW: Canadian Prius' odometers are in kilometers, not miles.[/quote]

Sooo, does that mean that theirs switches to mph or do they not get that choice?

Walt

 

[An04Prius]

My wife had the same thing happen to her and she called me up while she was driving down a country road saying "I am going 55 but it seams like I am standing still, what is wrong?!" I told her what button to push and it fixed the prob. But later she called me back and said it happened again! and I figured out that my security badge was hanging on it's lanyard from the rearview mirror swung and hit the button.

Man, that is one heavy security badge.

A twist on the story that happened to me: while in dealer for service, the tech left the speedometer set to kph instead of my usual mph. While driving home I noticed the weird reading, assumed I had to go back to the dealer to say they screwed something up during the service. I drove around like that for days waiting for a chance to take it back...until a friend pointed out what it was while I was griping to him about the dealer screw-up.

 

[iggy1iggy]

Man, that is one heavy security badge.

I have my IR badge, my SecrueID fob, the key to my desk, a pen, and my thumb drive on my lanyard so yes I guess that would be kind of heavy

 

[mrv]

BTW: Canadian Prius' odometers are in kilometers, not miles.

Sooo, does that mean that theirs switches to mph or do they not get that choice?

The Canadian MPH/kph switch will change the spedometer as expected. It will not change their odometer, though.

 

[Spike]

Which, now that I went to the car and checked, brings up the question as to why the odometer does NOT shift to kilometers when the kph button is engaged.

Just strikes me as odd that the speedometer can be shifted but not the odometer.

Is there a technician only switch buried in the entrails that places the odometer in to kilometers? If I recall correctly, Canada and Mexico still use the English miles system, but how about South America?

Walt

I think on the US cars, the mileage has to be in mileage by law, not kilometerage (?). The switch for the Speedo is there so when you drive in Canada or Mexico, you can still easily abide by their speed limit signs which are given in KPH. On a "normal" speedo, you have the kilometer markings on all cars for this reason. Many people near the borders constantly cross them for work and play. But in the end, it is a US car, and thus should always give distance traveled in mileage.

Spike