Ford Fiesta Mk6 - Checking battery voltage without measurement equipment 

While pressing odometer button, turn ignition key to "II" (ACC) position wait until "test" message appears. After "gage" and "led" test is completed press odometer button until you see "bt" followed by 3 digit number. At the video "bt 123" corresponds to 12.3 Volts battery voltage. (In fact multimeter is not needed, here it is used only to demonstrate that the voltage measured is equal to the voltage indicated on the display.)