Cruise Control Speed =/= Speedometer

[Sinister]

Mine is the same exact way. Speedometer shows 2mph faster than the cruise control setting. In my wife's 2013 Explorer the speedometer shows 1mph slower than the cruise control setting and in my 2012 Focus it was dead on the money.

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[anotherneon]

Yes, mine does that too. I took it to Ford who said everything was fine. I actually checked it via GPS this weekend and with cruise set to 60mph I was going down a hill and the GPS actually said 65mph as did the speedo all the while the cruise was still set at 60mph. Going up a hill the speedo dropped back to 60mph and matched the GPS and cruise. I personally think there is an issue, as does the gentleman in the Facebook group who got a ticket for speeding when his cruise was set to the posted limit.....

 

[Juben]

My EBM does this as well. When I set my cruise on 60 mph, the needle will show around 63. I don't know which to trust either. I thought it might have been the angle from which I was viewing the speedometer, but I moved around to look at it in about every possible way, but it's still off 2-3 mph.

I almost took it to my dealership, but when the recent blizzard we've had, I haven't moved the car and almost forgot about it. On the bright side, I guess I'm not the odd man out with this issue, lol.

 

[docbog]

I am very disappointed that Ford hasn't provided a Digital Speedometer yet.

All the data is there, it would be more valuable to me than some of the other displays, ie fuel to air, etc.

It is too bad we have to take a stand alone GPS with us in a car with so much technology including nav just to see digital speed!!

 

[Amaury]

No idea if the speedometer mechanism has changed since the last time I used to fly, but the way it works, (cable, magnet, etc) the speedometer will always show a difference of around 3mph or less compared to real speed by gps. Speedometers also need recalibration after certain time or if you change the tire size.

 

[Stangnut]

Anybody able to get this fixed yet?

 

[rotisserie_gold]

Same issue on 17 RS3. Reads 4mph lower on the cruise display than the spedo. I initially thought it was a Roush calibration issue until I saw the thread on here.

 

[Rod Schneider]

No idea if the speedometer mechanism has changed since the last time I used to fly, but the way it works, (cable, magnet, etc) the speedometer will always show a difference of around 3mph or less compared to real speed by gps. Speedometers also need recalibration after certain time or if you change the tire size.

No cables or magnets and such for a looooonnnnnggggg time.... Everything is electronically driven these days.

 

[HoosierDaddy]

Which one do we trust?

Maybe neither. But the cruise should be first choice because there can't be any physical alignment/calibration/viewing angle issues like with an analog needle. Don't know about Fords, but my Cadillac apparently re-calibrates the analog speedo every time the car's started because some times it is slightly below and sometimes slightly above the digital speedo/cruise.

The digital speedo (diagnostic mode) and cruise (when its at its "goal", which it won't always be) will be exactly right to the number of digits IF it knows the actual tire diameter. Of course tire diameters change as they wear or the manufacturer may take a close-enough approach to programming. But I think I read in the as-built thread that you can change the values that correlate to tire size if you want to compensate for wear or the differences with a different brand tire even if the same nominal size.

 

[speedfrk]

Mines off 2-3mph but in a safe way- cruise says 70, speedo 73 and cruise is dead on with gps.

 

[SAL-E]

My cruise control is dead on with my gps at all speeds. The speedo reads 2 high at 70mph. I can live with that.

 

[FordTechOne]

People only started to notice this "discrepancy" when digital speed readouts became commonplace. All analog speedometers have a built in tolerance. At 60MPH, its acceptable for the analog gauge to display 58-64MPH. It's not a matter of opinion; it's a matter of industry standard.

Therefore, if you're traveling at 70MPH, your analog speedometer may read 67MPH to 75MPH. GPS devices are not accurate; they simply base speed on distance vs time, not on actual vehicle speed.

The bottom line is the digital speed readout is the most accurate speed reading available as it's based on direct input from the vehicle's speed sensors; not a digital signal converted to analog or an estimated GPS speed reading.

 

[docbog]

Sooooo, as I stated last year has Ford seen fit to give us a Digital Speed via program since all the data is there. I for one would use it all the time as I do on my 2014 GMC Sierra. Certainly more than the air to fuel ratio and other data screens which I never use !!

 

[Nitronorth]

My cruise and speedo all match gps, however when i use the digital speed on the diagnostic screen its reads 12 km(1mph) lower..I guess I go buy a camaro!

 

[keltymd]

funny I have a loaner F150 while they yank the motor on my brand new 16 and its speedo and cruise are dead on. why is it off on the mustang??????????

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