I had the oil changed in my 2005 ford 500 and the oil change light won't reset back to the mileage info.

Try this

When they changed the oil they did not reset the light. The car needs to be told when the oil is changed.

when the warning comes on press the setup button. it should say press reset if new. Press the reset button. It should say if new oil hold reset. Press and hold the reset button until the display changes to oil life set to 100%.

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In most later vehicles, that light may stay on for a fixed number (it can be 5-50, we have both) of startups of the engine or many have to be manually reset. The engine can't tell the computer that it has fresh oil but will turn the light on after some finite mileage since the last reset for periodic maintenance items such as your oil change, but some items can't reasonably reset the computer; it has to be told that the oil was changed.
Check your manual to find how to reset that warning light and if you no longer have the manual for your vehicle, you can download a copy of it from the Ford website.

It means you need to get your oil changed, or they didn't reset it after your last oil change.

There is an info button. Press that button repeatedly until you get to maintenence. Once there, use the directional knob and toggle down to oil and press ok, from there it should either give you a reset tab to highlight and press ok, or highlight the mileage bar and toggle left until it is back at 0. If you have any trouble let me know and I will walk you through it. 

Hold mileage reset button down and turn key on. continue to hold button until dashes stop flashing and light goes out (approx. 10 seconds).

Press the setup button until "press reset at oil change" is displayed.
Then press and Release reset button until "hold reset to confirm" is displayed.
Now press and Hold reset button until "oil life set to 100%" is displayed.

Look to see if you have an Info Centre on your dash. If you do push the Info button until mileage comes up and click Reset it should change from english to metric. Changing the temp is done the same way. If you have an owners manual it will tell you how to do it as well. Hope this helps

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Oil Change Reset
A press of the OIL CHANGE RESET switch will allow you to
reset the oil life feature to 100% (or your Personalized Oil Reset
Percentage). After you have the oil changed, you must execute
the following procedure. Press the OIL CHANGE RESET switch
and hold for five seconds as the M/C counts down for five
seconds. After a successful reset the Message Center will display
“OIL LIFE RESET TO 100%.” If you have established a
Personalized Oil Reset Percentage, the display will show that
percentage instead of 100%. To ensure accurate oil life
indicators, perform this reset procedure only after an oil change.
Your Personalized Oil Reset Percentage allows you to establish a
smaller oil change interval than the manufacturer’s
recommended interval. To establish your Personalized Oil Reset
Percentage perform the following procedure:
1. Press and hold the OIL CHANGE RESET switch and press
the RESET switch while the display is still counting down
the 5 seconds to reset. The display will change to “START
OIL LIFE AT XXX%.”
2. Press the OIL CHANGE RESET switch until the displayed
percentage is the Personalized Oil Reset Percentage that you
desire. Your choices are 100%, 90%, 80%, 70%, 60%, 50%,
40% and 30%.