Speedometer giving false reading

Sitting Duc · 10-25-2007, 05:43 AM

Interesting.

I have the NZ(/AU, possibly JP derived) 2007 model, and have driven it about 300km; never touched the tyres.
On the drive home from the dealer, I noted that over my standard 5km "trip meter check", the odometer registered 5.2km. Given no more digits, that represents 103-105% of reality.
So for a "100km" journey on the MFD, I may have gone only 95km on the road.

A day or so ago, the local city council put up their famous radar "your speed is:" billboards on a road I pass daily. Checking the digital speedometer against that displayed by the radar, I find the Prius to display as much as 3kmph more than the radar, at 40-50kmph. Meaning to do 50kmph, the glowing green numbers afore me have to read 53.
So for a "100km" journey on the MFD, I may have gone only 94km on the road.

For my last car (1997 Toyota Corolla, so also based on a Japanese design / model / variant),
the odometer test was always less than 5.1km for 5km traveled, and the speedometer/radar was always spot on the money at 40, 50 and 60 kmph, even for an analogue dial. The city council refuses to put the billboards anywhere where I could get enough run-up for a 100 kmph test

Maybe I should have stopped by the policemen with the nice laser speed trap I saw this morning and asked them to check my speedo(meter) after all.

Given that both speedometer and odometer are misreading in the same direction, maybe by the same amount (3-7%); is it worth checking my (straight from the dealer) tyres to see if they agree to some sort of stated diameter? Or should I be content with starting a new topic about the great UN/Toyota conspiracy to upset non-US prius drivers?

ken1784 · 10-27-2007, 12:20 PM

<div class='quotetop'>QUOTE(Sitting Duc @ Oct 25 2007, 06:43 PM) [snapback]530138[/snapback]</div>

Quote:

Interesting.

I have the NZ(/AU, possibly JP derived) 2007 model, and have driven it about 300km; never touched the tyres.
On the drive home from the dealer, I noted that over my standard 5km "trip meter check", the odometer registered 5.2km. Given no more digits, that represents 103-105% of reality.
So for a "100km" journey on the MFD, I may have gone only 95km on the road.
[/b]

My test result was different.
The odometer was 0.2% error.
The speedometer was plus 6km/h error.

Ken@Japan

ronhowell · 10-27-2007, 09:06 PM

Hi All,

Just another input from the proud purchaser of a new 2008 model Prius. Rather than buy the optional Nav system at ~$2500 or so from Toyota. I purchased a Magellan Maestro 4040 GPS from Costco and installed it in the car.

My readings of both while driving around Southern Cal have shown an amazingly accurate correlation between the two, with no discernable difference in reading. I am surprised at the quoted 10% differences being shown on European Prii. In this day and age that is a major dicrepancy, that owners or Toyota should not be complacent about.

Ron

10-25-2007, 05:43 AM	#31
Sitting Duc Feathered Member Join Date: Oct 2007 Location: Hamilton, New Zealand Posts: 59 My Car: 2007 Prius Package: I-Tech Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Interesting. I have the NZ(/AU, possibly JP derived) 2007 model, and have driven it about 300km; never touched the tyres. On the drive home from the dealer, I noted that over my standard 5km "trip meter check", the odometer registered 5.2km. Given no more digits, that represents 103-105% of reality. So for a "100km" journey on the MFD, I may have gone only 95km on the road. A day or so ago, the local city council put up their famous radar "your speed is:" billboards on a road I pass daily. Checking the digital speedometer against that displayed by the radar, I find the Prius to display as much as 3kmph more than the radar, at 40-50kmph. Meaning to do 50kmph, the glowing green numbers afore me have to read 53. So for a "100km" journey on the MFD, I may have gone only 94km on the road. For my last car (1997 Toyota Corolla, so also based on a Japanese design / model / variant), the odometer test was always less than 5.1km for 5km traveled, and the speedometer/radar was always spot on the money at 40, 50 and 60 kmph, even for an analogue dial. The city council refuses to put the billboards anywhere where I could get enough run-up for a 100 kmph test Maybe I should have stopped by the policemen with the nice laser speed trap I saw this morning and asked them to check my speedo(meter) after all. Given that both speedometer and odometer are misreading in the same direction, maybe by the same amount (3-7%); is it worth checking my (straight from the dealer) tyres to see if they agree to some sort of stated diameter? Or should I be content with starting a new topic about the great UN/Toyota conspiracy to upset non-US prius drivers? __________________ If it looks like a prius and quacks like a prius...

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10-27-2007, 09:06 PM	#33
ronhowell Senior Member Join Date: Oct 2007 Location: Cypress, CA. Posts: 122 My Car: 2008 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 1	Hi All, Just another input from the proud purchaser of a new 2008 model Prius. Rather than buy the optional Nav system at ~$2500 or so from Toyota. I purchased a Magellan Maestro 4040 GPS from Costco and installed it in the car. My readings of both while driving around Southern Cal have shown an amazingly accurate correlation between the two, with no discernable difference in reading. I am surprised at the quoted 10% differences being shown on European Prii. In this day and age that is a major dicrepancy, that owners or Toyota should not be complacent about. Ron