Speedometer displays slower than car

These forums are specific to the Waze mobile app. Post here if you experienced a problem while using the app, have a question about the app functionality or a feature such as navigation or search.

Moderators: krankyd, Unholy

Re: Speedometer displays slower than car

Postby AlanOfTheBerg » Tue Nov 13, 2012 3:48 pm

In the 25-40 range, Waze and my Fusion align nearly perfectly, taking into account slight variations due to instantaneous changes on accel/decel.
Wiki Resources: Map Editing Manual | Oregon Project/To-Do List
Oregon-based US Country Manager | iPhone5 - VZ - iOS 7.0.6 | Waze v3.7.9.992
AlanOfTheBerg
Waze Global Champs
Waze Global Champs
 
Posts: 19467
Joined: Sat Aug 28, 2010 8:48 pm
Location: US Country Manager - Oregon, USA
Has thanked: 647 times
Been thanked: 2247 times

Speedometer displays slower than car

Postby BlazeTool » Tue Nov 13, 2012 12:42 pm

If you want to know your "actual" speed, take your car to a mechanic that will calibrate and certify the speed. (In the States, AAA will certify speedometers).

Slight changes in tire size can make a significant change in speedometer readings.
BlazeTool
 
Posts: 141
Joined: Wed Jun 20, 2012 5:40 pm
Location: Columbus, OH
Has thanked: 0 time
Been thanked: 2 times

Re: Speedometer displays slower than car

Postby crazed_out » Sat Nov 10, 2012 5:04 pm

This is true! A speedometer in a car is supposed to show that you're going faster than you really are. As much as up to 10%, but it' very different from make to make. Trucks (lorries) and busses have a speedometer that are much more precise than cars. Hence the reason for you driving and getting a truck or bus up close behing you. In my Volvo the difference is 5 km/h up to about 50 km/h then as much as 10 km/h between 70 and 120, after that I don't know because we're not allowed to go faster in Sweden. 8-)
Area Manager in Sweden, parts of Västra Götaland (West Sweden).
Samsung Galaxy Note II GT-N7105 (4.1.2 stock) | Volvo 850 T5 -96 med +25000mil | Nissan Micra -04 10000mil
crazed_out
 
Posts: 142
Joined: Wed Feb 08, 2012 9:24 am
Has thanked: 9 times
Been thanked: 6 times

Re: Re: Speedometer displays slower than car

Postby dmcconachie » Sat Nov 10, 2012 8:11 pm

islupepa wrote:One of the reason for displaying wrong speed could be this conversion bug...http://world.waze.com/forum/viewtopic.p ... conversion

Firstly, it's not displaying the wrong speed. As mentioned above, your car almost definitely overstates the speed.
Secondly that conversion bug creates at most a rounding error. It's only noticeable because it means certain integer values are not displayed. Certainly not enough to be perceptible though!

via Tapatalk
dmcconachie • UK Country Admin • Forum Moderator • Former Global Champ
Nexus 4 • Android 4.3
UK WikiFB PageForum FAQCurrent status
dmcconachie
 
Posts: 6019
Joined: Sat May 22, 2010 11:44 pm
Location: Edinburgh, UK
Has thanked: 80 times
Been thanked: 260 times

Re: Re: Speedometer displays slower than car

Postby dmcconachie » Tue Nov 13, 2012 6:36 am

Sahirsiddiqui wrote:My experience is that both Waze (& my old Garmin GPS) show speeds almost exactly 10km/hr slower than my actual speed.

"Actual" measured by? If your car then this is normal and waze will actually be closer to your actual speed.

via Tapatalk
dmcconachie • UK Country Admin • Forum Moderator • Former Global Champ
Nexus 4 • Android 4.3
UK WikiFB PageForum FAQCurrent status
dmcconachie
 
Posts: 6019
Joined: Sat May 22, 2010 11:44 pm
Location: Edinburgh, UK
Has thanked: 80 times
Been thanked: 260 times

Re: Speedometer displays slower than car

Postby Froggypwns » Tue Nov 13, 2012 4:33 am

My first hand experience shows Waze to often report 1 or 2 MPH slower than actual. My car will say 60, my Garmin will say 60, then on my Xoom tablet Google Nav will say 60, GPS Test will say 60, and Waze will say 58. Fire up my other tablet, Google says 60, Waze says 58. Even on my old Windows Mobile phone, it will say 58 on Waze and 60 on Google Maps.
Froggypwns
 
Posts: 80
Joined: Tue Apr 03, 2012 8:24 pm
Has thanked: 0 time
Been thanked: 7 times

Re: Speedometer displays slower than car

Postby islupepa » Sat Nov 10, 2012 8:01 pm

One of the reason for displaying wrong speed could be this conversion bug...viewtopic.php?f=15&t=7803&hilit=speed+conversion
Motorola Defy, Android 2.2.2, Waze 3.6.0.0
islupepa
 
Posts: 101
Joined: Fri Jan 07, 2011 8:38 pm
Has thanked: 0 time
Been thanked: 0 time

Speedometer displays slower than car

Postby jasonh300 » Sat Nov 10, 2012 1:24 pm

Try your Drive A Mile test again. Divot based on mile markers in a different location.

Car speedometers generally read high to keep you out of trouble. My Chevrolet reads a few MPH higher than Waze, and my BMW reads about 5 or 6 MPH higher when going over about 45.

I've tested Waze against those "Your Speed" radar advisories and its pretty accurate.




---------
Via my iPhone 3GS.
Image
New Orleans, Louisiana
Regional Coordinator, South-Central Region
Waze FAQ ... Best Map Editing Practice ... Waze chat on IRC.
jasonh300
Waze Global Champs
Waze Global Champs
 
Posts: 6868
Joined: Fri Oct 28, 2011 4:26 pm
Location: New Orleans, LA USA
Has thanked: 239 times
Been thanked: 628 times

Re: Speedometer displays slower than car

Postby jasonh300 » Sat Nov 10, 2012 6:08 pm

Lonewolf147 wrote:
jasonh300 wrote:Try your Drive A Mile test again. Divot based on mile markers in a different location.



OK, I'll try it again in a few different locations.

Thanks everyone else for the input. 8-)


Oh, that's another point I wanted to make. The mile markers along the U.S. interstates are very inaccurate. I was checking them against my odometer one day and there would be .8 miles and then the next one would be 1.2 miles. They place the signs where it's convenient, so they're not always exactly where they're suppposed to be.
Image
New Orleans, Louisiana
Regional Coordinator, South-Central Region
Waze FAQ ... Best Map Editing Practice ... Waze chat on IRC.
jasonh300
Waze Global Champs
Waze Global Champs
 
Posts: 6868
Joined: Fri Oct 28, 2011 4:26 pm
Location: New Orleans, LA USA
Has thanked: 239 times
Been thanked: 628 times

Speedometer displays slower than car

Postby Lonewolf147 » Sat Nov 10, 2012 8:04 am

I did a search an found this thread from 2010, http://it.waze.com/forum/viewtopic.php?f=7&t=7147, but it didn't look like anything was decided or fixed.

My wife and I both have a Droid 4 (previously used Droid 1's) running the latest ICS. For the past several years that we've been wazing, the onscreen speedometer has always shown a speed 2mph slower than what our vehicles show. This has happened in every car we've driven, so it seems to be related to the Waze API and not the vehicle.

I've done the 'drive a mile' test and have confirmed my results that waze is reporting 2mph slower than my actual speed. I've also ran other GPS programs on my phone and they do show the correct speed of my vehicle. That tells me that my phone is correctly measuring my speed and again points to the Waze API as having an issue.

Has there been any other work or discussion of this issue that I'm not finding on the forum? Has this problem been duplicated with anyone else recently?
ImageImage
Image

Motorola Droid 4, rooted
Lonewolf147
 
Posts: 74
Joined: Sat Feb 27, 2010 6:01 pm
Location: Milwaukee, WI, USA
Has thanked: 3 times
Been thanked: 5 times

Next

Return to Waze App

Who is online

Users browsing this forum: Teslafied