Speedometer reads fast

thedude

Well-Known Member
Joined
Aug 30, 2019
Threads
8
Messages
460
Reaction score
297
Location
USA
Car(s)
NONE. BOUGHT BACK - 2020 Absolute Zero 3.0 Premium
I’m seeing a consistent 2mph over indication in my Supra.

Waze agrees with the “your speed is xx” signs which are 2mph lower than the car.

This accelerates depreciation and also causes warranty and service windows to close faster than they should. I believe there have been class actions about this sort of thing in the past.

Anyone else have a fast speedometer?
Sponsored

 

A70TTR

Well-Known Member
Joined
Sep 9, 2017
Threads
8
Messages
2,727
Reaction score
10,052
Location
Japan/EU/USA
Car(s)
ST205 GT4, JZA70, JZA70 TT-R, S210 Athlete
I honestly don't own a single vehicle where the speedo doesn't read a bit faster than I'm actually traveling; it's generally 2-3mph over at highway speeds

what other vehicles have you owned where this is not the case?



EDIT: I just asked a few people around me and all said this is completely normal behavior (which has always been my impression).
 
Last edited:
OP
OP

thedude

Well-Known Member
Joined
Aug 30, 2019
Threads
8
Messages
460
Reaction score
297
Location
USA
Car(s)
NONE. BOUGHT BACK - 2020 Absolute Zero 3.0 Premium
I honestly don't own a single vehicle where the speedo doesn't read a bit faster than I'm actually traveling; it's generally 2-3mph over at highway speeds

what other vehicles have you owned where this is not the case?



EDIT: I just asked a few people around me and all said this is completely normal behavior (which has always been my impression).
My last car (Audi S4) was pretty spot on.
 

Illsic_Design

Well-Known Member
First Name
Josh
Joined
Jun 8, 2018
Threads
1
Messages
173
Reaction score
240
Location
Nor-Cal
Car(s)
E92 335i N54, 4G63T Mighty Max
This is spot on for being a BMW. They are known to be like 1-2% off, as I beleive in Germany the automaker can be fined if the speedo reads lower than the car is going. On my 335i this can be changed with coding, not sure on the newer cars. I actually prefer it this way since when my speedo says I'm going 80 or so I'm actually going a little under 80 and usually CHP won't bat an eye for under 80, so helps me with speeding tickets.
 

s219

Well-Known Member
First Name
Doc
Joined
Jun 22, 2019
Threads
2
Messages
528
Reaction score
635
Location
Virginia USA
Car(s)
BMW X3 M40i, BMW M2 Comp, Ferrari 328
I’m seeing a consistent 2mph over indication in my Supra.

Waze agrees with the “your speed is xx” signs which are 2mph lower than the car.

This accelerates depreciation and also causes warranty and service windows to close faster than they should. I believe there have been class actions about this sort of thing in the past.

Anyone else have a fast speedometer?

+2mph is the standard for BMW speedos. How the heck would this have anything to do with depreciation? It doesn't affect the odometer, just the speed displayed to the driver.
 

084runnerltd

Well-Known Member
First Name
Jake
Joined
Feb 15, 2019
Threads
17
Messages
452
Reaction score
495
Location
ND
Car(s)
08 4Runner / 99’ Lexus LX470 / Deposit 2020 Supra
Vehicle Showcase
3
All BMWs read 2-3mph fast...
 
OP
OP

thedude

Well-Known Member
Joined
Aug 30, 2019
Threads
8
Messages
460
Reaction score
297
Location
USA
Car(s)
NONE. BOUGHT BACK - 2020 Absolute Zero 3.0 Premium
+2mph is the standard for BMW speedos. How the heck would this have anything to do with depreciation? It doesn't affect the odometer, just the speed displayed to the driver.
Can’t say if it does or doesn’t affect the odometer. In more traditional analog odometers, higher speed certainly does impact it and runs up mileage faster.

I’d wonder why, if they can make the odometer correctly indicate the distance traveled, they’re unable to make the speedometer display accurate velocity. Unless over-indicating speed was by choice, why not use the telemetry used by the odometer?
 

Illsic_Design

Well-Known Member
First Name
Josh
Joined
Jun 8, 2018
Threads
1
Messages
173
Reaction score
240
Location
Nor-Cal
Car(s)
E92 335i N54, 4G63T Mighty Max
Can’t say if it does or doesn’t affect the odometer. In more traditional analog odometers, higher speed certainly does impact it and runs up mileage faster.

I’d wonder why, if they can make the odometer correctly indicate the distance traveled, they’re unable to make the speedometer display accurate velocity. Unless over-indicating speed was by choice, why not use the telemetry used by the odometer?
as I (and others) stated above, it is because in Germany the speedo CANNOT read slower than the speed you are going, EVER, so they play it safe by making it read fast. All manufacturers do this, some to a lesser or greater extent.

See the article for clarity; https://www.thrillist.com/cars/your...accuracy-in-german-american-and-japanese-cars
 

s219

Well-Known Member
First Name
Doc
Joined
Jun 22, 2019
Threads
2
Messages
528
Reaction score
635
Location
Virginia USA
Car(s)
BMW X3 M40i, BMW M2 Comp, Ferrari 328
Can’t say if it does or doesn’t affect the odometer. In more traditional analog odometers, higher speed certainly does impact it and runs up mileage faster.

I’d wonder why, if they can make the odometer correctly indicate the distance traveled, they’re unable to make the speedometer display accurate velocity. Unless over-indicating speed was by choice, why not use the telemetry used by the odometer?
It doesn't affect the odometer and you can prove this to yourself very easily if you don't believe me and all the prior BMW experience.

The speedometer offset is not an error or due to difficulty measuring speed, it's an intentional software tweak to make it read high to the driver. As mentioned, it's done for legal reasons. If you code the car, you can actually change the artificial offset or zero it out.

Both the speedometer and odometer are reading from the transmission, but unlike old mechanical systems that ran a cable up to the dash, it's a sender that converts to an electrical signal and then it goes on to the central computer via wire.
 
OP
OP

thedude

Well-Known Member
Joined
Aug 30, 2019
Threads
8
Messages
460
Reaction score
297
Location
USA
Car(s)
NONE. BOUGHT BACK - 2020 Absolute Zero 3.0 Premium
It doesn't affect the odometer and you can prove this to yourself very easily if you don't believe me and all the prior BMW experience.

The speedometer offset is not an error or due to difficulty measuring speed, it's an intentional software tweak to make it read high to the driver. As mentioned, it's done for legal reasons. If you code the car, you can actually change the artificial offset or zero it out.

Both the speedometer and odometer are reading from the transmission, but unlike old mechanical systems that ran a cable up to the dash, it's a sender that converts to an electrical signal and then it goes on to the central computer via wire.
Yeah I understand that it’s reading telemetry. Just odd that they would choose not to indicate the actual speed. I haven’t researched it so I’m not mistrusting the collective experience, I’m simply not familiar with it. Thanks for the lesson.
 

zamiel

Well-Known Member
First Name
Rick
Joined
Sep 6, 2019
Threads
4
Messages
53
Reaction score
58
Location
Massachusetts
Car(s)
1991 MR2 Turbo, 2018 Honda Civic Sport, 2020 Supra
I just got my Supra last weekend and noticed this for the first time yesterday when comparing Waze to the speedometer. I've never noticed more than a 1 mph discrepancy on any of the Japanese cars I've owned. I figured there had to be a way to calibrate the speedometer, but it sounds like this is the norm based on this thread. I also came across this BMW thread that seems to confirm that this is normal: https://f87.bimmerpost.com/forums/showthread.php?t=1448247
 

Famo

Well-Known Member
First Name
Justin
Joined
Nov 23, 2019
Threads
2
Messages
59
Reaction score
17
Location
South Florida
Car(s)
2020 LE Supra
Bumping this. Does anyone know if you can code this in bimmercode under the "display options for the instrument cluster." Either the digital speed correction option or the "digital speed in board computer. Would appreciate if anyone can help. Thanks.
 

Kiwi Greg

Well-Known Member
First Name
Greg
Joined
Nov 28, 2019
Threads
7
Messages
405
Reaction score
421
Location
New Zealand
Website
terminatorproducts.co.nz
Car(s)
2020 Supra, 2021 GR Yaris, 2022 GR86
I have noticed this for quite a few years & vehicles over here, usually 5-8 kph under right from the get go all through the range

Quite frustrating, what's wrong with showing the accurate speed in a brand new off the lot factory car ?

I guess its a win for the Govt because everyone is going slower than they think & a win for the manufacturer as the car appears to go faster that it actually does

My Supra indicates 2.5kph fast with 285/30 x 20 tyres
 

Famo

Well-Known Member
First Name
Justin
Joined
Nov 23, 2019
Threads
2
Messages
59
Reaction score
17
Location
South Florida
Car(s)
2020 LE Supra
I have noticed this for quite a few years & vehicles over here, usually 5-8 kph under right from the get go all through the range

Quite frustrating, what's wrong with showing the accurate speed in a brand new off the lot factory car ?

I guess its a win for the Govt because everyone is going slower than they think & a win for the manufacturer as the car appears to go faster that it actually does

My Supra indicates 2.5kph fast with 285/30 x 20 tyres
I agree, but im pretty sure with one of the options I mentioned in coding with bimmercode it can be coded to the show the actual speed you are going not the fast one it shows. Just not sure which one exactly is it, guess I'll have to experiment.
Sponsored

 
 




Top