Im just off out now but tomorrow evening if my advice doesn't work then will try and search it for you.

If the LCD display is like the Focus' then how you work it is...

Put your key in, turn it once to the radio click.
Press the button in the middle of the display (one that you reset your milage with)... Keep it held in, turn the key to the ignition position, keeping your finger on the milage zero button for about 5-10 secs... you will see all the speedo and rev counters fly right to the end of the scale, then go back to normal...

You are now in the ecu, click the button once, this will take you onto each mode... i.e Milage, Digial Speedo, Digital Rev Counter... its quite useful really.

If this is the case, when you turn the ignition off, it will all reset back to milage again.

Hope this helps, no harm in trying.