Anyone know how to calibrate the speedometer? Is that possible? Is there some menu you can set the wheel size?

For some reason my speedometer is fast. It reads 70mph, but actual GPS speed is 65. When it reads 60 actual speed is around 56. Maybe it thinks I have 18" rims?
Any ideas? It has the stock R52 rims. 17".

Thanks

 

There's a baked-in offset that the computer adds to the actual speed. I was able to remove it from my digital speedometer, but I never figured out how to fix the center one. I believe mine only read ~3 mph high though.

 

Ssshhhh! Hush or she will hear you!
My daughter still has no idea her speedo reads 6MPH high at highway speeds. I have no intention of telling her or correcting the problem. LOL.

 

+1 size 215/45R17 tires nicely correct majority of error at highway speeds.
Check brand specs - only slightly taller/wider than OEM 205/45R17...

 

Makes sense, we are running 205 / 40 / 17 on Alice so I expected things to be a bit off.

 

-1 size 205/40R17 Toyo RA1 DOT track tires were on mine when purchased May 2021, which were nearly "new" but aged-out and stiff. Happy to have ditched those late last year!

 

So they purposely read low at highway speeds ??? Also can it be corrected via tuning ??? Im used to it but I'd like it to be correct

 

^^^ "Purposely" reads high vs low. If you have a Garmin Nuvi or similar, compare speedo reading vs GPS to determine...

 

Or the speedometer app on iPhone… I corrected the digital one in obc via coding, but the big center “analog” one seems to not have a similar adjustment in coding. So it’s going to stay 3 mph fast until someone smarter than I figures it out… if ever.

I think your issue op additionally is the wrong sized tires compounding the fixed 3 mph error.

should be 205/45/17.

 

derderder that's what I meant...yea i found mine says I'm going about 6mph too fast , I figured my 16s had part to play in that...I just got used to it and guess it is what it is

 

I run 215/40 ZR 18s & when I go by those radar detectors in the middle of the road (sleeping policeman) my speedo is on the money. GO FIGGER

 

hmmm, 1st time I've seen the thread. I thought everyone knew that the European union mandated that little indicator error. I just set the cruise control at +5 of the speed limit and go.