Well, there's no doubt that the odometer and speedometer are interconnected - they both use the same signal from the wheel-speed sensor.

The question is whether or not the car's computer system can/does apply different correction factors to the wheel-speed signal for the odometer and speedometer displays. There's no reason to automatically assume that a speedometer error imples an odometer error, (except for the portion of the speedometer error that results from using non-standard diameter tires).

I just re-checked mine last month against my GPS on a long straight flat section of I-40. I compared the elapsed mileage on the car's odometer to the elapsed distance readout from the GPS over a one-hour period, and they differed by less than half a percent. Meanwhile, my speedometer was reading about 5.5% high. I had a 10-satellite lock on the GPS the entire time.

EDIT - You can even do a simple check without a GPS. Find a straight section of road, set your cruise control for 65MPH, reset your trip odometer, and wait exactly one hour. At the end of the hour, I'll bet that your trip odometer shows fewer than 65 miles.

 

All I am saying is that even MINI won't confirm that the odometer is not 10% off, they cannot/will not tell me how it reads.

It simply comes down to the fact that I feel like MINI is hiding something from me and despite absolutely loving the car, if I can't trust the dealership there is no point in keeping it.

 

There are lots of folks who trust the dealership about as far as they can throw them and still keep their cars But I understand your reasoning. The best we (as fellow enthusiasts/owners) can do is try to make you feel better about it.

 

If MINI/BMW were to negligently/purposefully install odos that racked up abnormally high mileage, they would open themselves up to a lawsuit: a class action suit that they would likely lose. I doubt that your odo is more than 2-3% off...but you could have it tested, I suppose. See article...at this link
http://www.autoblog.com/2007/02/19/o...-million-cars/

 

Mine is actually off the other way. Whenever I go through a speed trap that shows how fast I'm driving, it's usually 3-4 mph faster than what my speedo shows.

 

Out west, some of the freeways have signed and measured measured five-mile segments, specifically for the purpose of calibrating your speedo/odo. This provides independent confirmation for the use of other methods - my GPS is in very close agreement on both speed and distance with the measured mile near me. On my car, the speedo reads about 4% high, while the odometer is within one percent with my current wheels and tires. Close enough for me.

BTW, no manufacturer calibrates their speedometer to read too low - if they did, owners would quickly blame and sue them for the speeding tickets.

If you want to change the percentage by which the speedo is off, change your tire and/or wheel size. Of course, then your odometer will be off by whatever percentage you changed the diameter of the wheel/tire.

Your dealer can adjust the computed mileage to agree with the odometer, if it doesn't already. Adjusting it to match the speedo would be pretty pointless, as the speedo is an instantaneous reading, while the computed mileage only changes every second or two - they could never be in sync.

 

The dealer isn't hiding anything from you - they most likely don't know the technical details of how the odometer and speedometer interpret the wheel-speed signal and adjust it to display your speed and mileage.

Try going to a Honda or Chevrolet dealer to find out the same thing about the Accord or the Cobalt - I doubt you'll have any better luck. If anyone can tell you, it will probably be one of the engineers at MINI, and good luck getting hold of one.

There are several ways to check your odometer accuracy, and the dealer can calibrate your speedometer, but expect to pay for it unless the speedo is outside of the allowable tolerances.

 

This discussion has been going on in various threads for several years and there has been no agreement in that time.
There are several facts that one should know however,

(1) The speedometer is NOT 100% accurate at any time and if they could make one that was you would not want to pay for it. They are like gas gauges on airplanes, they are only required to be accurate when the tank is empty. In fact if you look at the speedo when you are stopped it probably does not say exactly "0".

Many people have checked their MINI speedo by various methods and the usual error is about 2% to 4%. There is no federal law which states what the maximum error allowed is but there is a voluntary agreement among car makers to a maximum of 4%. In Europe the speedometer is REQUIRED to read faster than actual speed.

In my Oct 06 "S", an indicated RPM of 3000 shows 73 MPH on the speedo but is actually arounud 70 MPH. Indicated speed can be effected by tire size, tire air pressure, and speedometer age to name a few.

Another factor is how you fill the tank, up to the tippy top or auto shut-off method. Then there is the lead foot factor that most of us know about.

In fact the mini made before July of 07 has a device to indicate a low tire by counting tire revolutions on each side of the car and comparing them and it does not take a large change in the pressure to show a low tire.

By the same token, the GPS method is not foolproof either because the GPS system has an error built in on purpose for military reasons.

Using the stopwatch and mile markers is probably as good as any and since you live in MO you even have the 1/10th mile posts to work with.

It is well known that the OBC is somewhat optimistic compared to the hand calculated method but I have found that my OBC is still fairly close to the hand calculated figures.

I missed what MPG you are getting but if its an 06 "S" then high 20's average with low to mid 30's over the road is about par for the course. If it's an 07 then maybe a little better than that. If you have a MPG factor of +-30 and a fun factor of WOW, what more can you ask for? There are a few cars that can out MPG of the MINI but very few that have a better fun factor.
Enjoy!!

 

The intentional error you're talking about is called "Selective Availability", but it's been turned off for almost eight years - there's no longer any intentional error built into GPS signals.

In theory, SA *could* be turned back on in the future, but there are no plans to do so, and it's unlikely, considering how widespread the commercial and consumer use of GPS has become.

Civilian GPS units are as accurate as the ones the military uses. There *is* a military-only feature called the "M-Code", but it deals with anti-jamming and signal-strength issues, not accuracy.

 

Mine reads high too. 100+ and the cop clocked 91

 

"...the GPS system has an error built in on purpose for military reasons..."

Not true for the last several years. Newer GPS units are accurate to as little as 9ft, which gives very accurate computed speed and distance.

 

OK...enough already. So the GPS system was changed..thanks to Clinton but that was only one of seveal points I made in that post. The point is that no speedometer is perfect and we wouldnt pay for one that was.. Most speedometers are real close at one point or another and then get worse on the ends. LETS NOT GET TO WORKED UP ABOUT THIS....sorry didn't mean to get excited!!! There are things worth getting excited about but this may or may not be one of them. Have a nice day and motor on

 

To your point about calibration, it's part of German law that a Speedo can not read low. The allowable error is only on the high side. This is to prevent owners from blaming the car. Now, if you change wheels/tires/transmission ratios, etc, then we're talking about a different ball game. But for stock, right out of the factory, I believe all manufacturers protect themselves by ensuring the speedo is never low.

 

Good points.
MINIs are no different in speedometer error than any other brand.
If it bugs anyone you will likely have the same pains with any car.

 

My speedo is reading about 7% over, judging by my GPS. I would drive 80mph to and from work aligned with traffic in my Audi. With my Mini, everyone sped up to 85mph, apparently. Checking against my GPS, there was a flat 5mph difference at 75mph. Makes me crazy.

Because the federal limit is 5%, I am going to take it in for service along with my sun roof alignment problem. A couple of miles per hour is fine, but I am not convinced that the odometer isn't tied to the error.

 

Could you post a link to the federal guidelines you're referencing? All I've seen in an official document are the Euro guidelines, but I can't imagine the US ones being tighter.

EDIT - Never mind, I found it. There's no federal DOT-prescribed limits on speedometer error. The only requirement is that automakers have to conform to *either* the SAE rules (J226) *or* the Euro spec rules (ECR-39) for speedometer accuracy.

The Euro rules are looser (-0% / +10% plus an additional ~2 MPH) but as long as an automaker is within them, they're legal.

 

United States

Not always a Wiki fan, but: http://en.wikipedia.org/wiki/Speedometer



"As of 1997, Federal standards in the United States allowed a maximum 5% error on speedometer readings (per "Auto Tutor", American Automobile Association of California magazine, Oct. 17, 1997). Aftermarket modifications, such as different tire and wheel sizes or different differential gearing, can cause speedometer inaccuracy."

 

All, I have checked, double checked and rechecked the speedo and it is off by a factor of 9% to 10%.

I have contacted MINI USA and they refuse to do anything to solve the issue.

I have a new Mustang whose speedo is off by less than 2% and an old Mustang whose speedo is off by less than 3%. We have a Dodge duelley that is off by less than 1%. For crying out loud, I have a mid-80's Maserati that is more accurate than my MINI.

I really find it hard to believe that the dealership cannot recalibrate it for me. I am just truly irritated that MINI will not do anything at all about it.

So, it will be sold.

 

Similar discussion over at the 2nd generation forum. If the odometer reflects the speedometer readings, the mileage calculated for warranty service will over report and constitute a "taking" from the client. The result is cars coming off warranty earlier than they are supposed to.


Smells like class action to me.

 

Per GPS our speedometer reads 38 mph at 40 and 57 mph at 60. This means that the delta increases with speed. Additionally, I would expect the accuracy to vary with tire wear since I can't imagine a way for the engineers to adjust for assumed tire wear.

We also have a 2002 Honda Odyssey, and Honda lost a class action law suit because their odometers were showing warranty expiration early. Honda ended up extending the warranty by 5% (see http://www.nytimes.com/2008/03/30/automobiles/30MILEAGE.html).

We had a simple issue (dash clock backlight went out) a few hundred miles after the warranty expired, and the dealer fixed it anyway, describing it as a "good will" repair--and that was before the lawsuit. The smart way for MINI to deal with this is to simply honor warranty repairs for an additional percentage and take credit for being honest and reaching out to customers. I figure if I have a positive dealer experience right after warranty expires, I'm much more likely to stick with dealer service than to defect to an independent.

 

This I believe, my speedo (06 MCS) is off, the faster it says I am going the less it is accurate 90 indicated is something like 83 I think...

 

My car reads about 5% high with the tires I'm using.

If one is really serious about correcting the speedo, there is a black-box that can be plugged in between the speed sensor and the computer - the Electronic Ratio Adapter - http://www.abbott-tach.com/era.htm

I used one in a RX-7, and it worked well.