Has anyone ever had their onboard computer give an "Average MPH" that's totally out to lunch?

My wife called from a road trip to tell me that her average speed reported by the OBC was 1.2 MPH. She said that earlier in the day, it had been as low as 0.8MPH.

She re-set the average MPH, and it seems to be working now.

The only thing out of the ordinary is that she hasn't reset the average MPH since we bought the car new (about 7,000 miles).

I'm curious if this has happened to anyone else?

 

Did it say MPH or Mach?


It sounds odd never heard of it happening before, I'd mention it next time you're at the dealer, just in case its a sign of somehting larger.

Does she (and you) wait until the fuel empty light is done with its checks before starting the engine? I know of several cases just taking that extra second eliminates many electrical gremilins.

 

I wait for the empty light to go out on my car, but she doesn't on hers. I figured there's no need to burden her with it unless there was a solid reason. She's been driving the car since new without anything weird happening before this.

I'll mention the MPH glitch to the dealer when we take it in for the first service here in a few months and see if there's a diagnostic they can run.

I'm also wondering if perhaps the OBC isn't designed to go so long without the Average MPH feature being reset. It could be something as simple as a register in the computer not having enough bits to store the required values.

 

For the most accurate readings on the OBC, suggest that she reset it every time she fills up the tank. 0.8 mph!

 

Note that the MINI calculates MPH based on the time the car is running. So if she was idling for a long time, that would affect it. (But likely not THAT much!)

 

i have the same problem. how do i reset it?

 

Get the OBC on the desired value then press and hold the OBC button for a few seconds untill it resets.

 

Avg MPH over 7000 miles could likely be that low. Take into account all time spent idling as well as stop&go traffic. I have yet to find a use for that info, so I generally ignore that function.

 

The car was built in early April, and has about 7,000 miles on it. To average only 1.2 MPH, the car would have had to been running constantly since about mid-March - two weeks before it was even built!

Idling and stop-and-go traffic *does* drop the average significantly, but not that much. Our average is usually around 25-28 MPH for both cars.

I'm with you, though - the "Average MPH" function does seem pretty useless, unless you're trying to correlate your average speed with your average fuel economy over a tankful of gas or something like that.

 

I reset my MPG AGS every time while driving car not sitting still

 

It happened to mine once too - My averages are incredibly stable - 24.5mpg and 29.9mph - for no reason at all - it was displaying very similar figures.

The next time it was in for a service I mentioned it to the SA and he said that he had heard of it before and would check it out. When I went to pick it up they said that they had not found any error codes, but if it happened again to NOT reset it, but to take it in and they would take a look.

Of course 30K later it has not happened again......

 

Mine has reset itself a couple times usually after about 6 or so months it seems. I think there is a maximum amount of miles it can go before it just messes up and you need to reset it.

 

Slightly different comment related to mpg on the OBC. Mine consistently read about 20% high, so I naturally diagnosed it as using British imperial gallons, but I couldn't figure out how to fix it.

Answer was to set the LANGUAGE to English (US). I never noticed it was set to English (UK) and never thought the language setting would change the units of measure for the OBC--but it does.

Just FYI for anyone as thick as me.

 

Oooh, good point! I'll tell the wifey and she can check hers out to see if it's set to UK also. There is a constant 2mpg diff between OBC and hand calculated mileage on her car too... ok, not 20%, but I wonder.

Good tip.