What year is your Fiesta?
Why?
The KEY you have may be "blocked" by the SYNC system seeing it as a Restricted key. This may prevent you from making ANY changes to any sub-system like CLOCK or DATE because the KEY is seen by the system as a LIMITED ACCESS key. You may need to refer back to your owners manual and look under MYKEY.
IF you are not blocked...then the following may help...
Some Fiestas have SYNC...which is a menu-driven module that shares the display with the Audio and use the "OK" button to process the commands you bring up using the MENU KEY - if you're resetting the Clock in a Fiesta that has SYNC - HIT "OK" button once you have the Hours and Minutes set - then hit the "Left" or "< arrow." to exit back out - up, a "branch" of the tree at a time (Previous Screens - like hitting your Browsers' Back Button)
There are also 4 buttons on the bottom of these "SYNC" systems...
They show up on the display on the bottom of the screen like 4 tabbed labels...
Those 4 - correspond to the 4 buttons below the OK button and are close to the Door LOCK and HAZARD warning flasher buttons. 2 on one side, two more on other side...
Turn the key on to Position I or II or just START up the engine and allow the car to continue to "boot".
Then turn on the Console (Press POWER)...
The following is REDUNDANT for some, others can possibly use it to help them locate and use features as they see fit...
The next pics are while the vehicle is idling and POWER ON for Console - yes it's dark outside - so this improves the CONTRAST but gives you some "blurry" pics - work with me here - I'm working with a limited budget, as in I won't charge you - its' FREE - I took 15 minutes of my day to help you...so just be thankful ok? No Flames...
Bring up the MENU
If you hit "CANCEL" - or the first button in the row below all those other keys on the keyboard, that will skip the whole process and return you to the main screen and NOT save any changes...
But, you need to get to Settings...
So this (the following) is the process I use and it has not failed me yet - I only had to do this twice, because I disconnected the Battery to clean it's contacts...a story for later...
But once I stored the Clock Settings using OK, it has kept proper Time and Date as long as the car's Battery stays charged...
Here is what works for me...
View and Follow Along as you need...
Console POWER ON -
Press MENU button...
SYNC II gives you something like this...
Pressing OK on CLOCK SETTINGS row -
Brings you to this...
Now just Cursor' over to the part you wish to SET...Press OK...
In this case - TIME
Once you have your CLOCK or DATE or BOTH set...
YOU PRESS OK on this screen to ACCEPT changes you made.
The Screen automatically goes back to the CLOCK SETTINGS MENU...
So if DATE and TIME are showing correctly - you are essentially done.
Just LEFT ARROW out to Main MENU...
Don't POWER DOWN (Turn Console OFF or TURN OF THE IGNITION ) - you must exit the SETTINGS back to a FUNCTION. POWER must remain on until you have restored your original screen - PRESS A FUNCTION key to restore to that condition you want the CONSOLE to be in when you turn the POWER back on or when you Start the engine - leaving the Console to power up in that mode.
You can either wait for the screen to change back to your original POWER setting, or you can just press the FUNCTION key to return to that portion of your Console and your entertainment...
Once you have the Main screen of the FUNCTION you want to power up in, you can POWER DOWN - turn off the IGNITION and remove the key.
You will find that pressing OK seems to toggle in between screens, it may annoy you but pressing a FUNCTION key gets you back to your main Console - just remember that if you DONT press OK - nothing gets saved...
Make a mistake? Just - powering OFF the Console can help you in restoring back to a previous setting or keep damage to a minimum.
I hope this helps!
I'm still learning about my own vehicle so enjoy the fun learning yours - I feel your Pain!