Erasing HomeLink buttons

To erase the three programmed buttons (individual buttons cannot be erased):
• Press and hold the two outer HomeLink buttons until the indicator light begins to flash-after 20 seconds. Release both buttons. Do not hold for longer that 30 seconds.

HomeLink is now in the train (or learning) mode and can be programmed at any time beginning with Step 1 in the Programming section.
See also:
INTERIOR
The MKZ Hybrid's interior is where it really shines. Not literally; it
literally shines on the outside with all that chrome. On the inside there's a
little shine but mostly some luxury-type touche ...
Speed control
With speed control set, you can maintain a set speed without keeping
your foot on the accelerator pedal.
WARNING: Do not use the speed control in heavy traffic or on
roads that are winding, slipp ...
Four-wheel anti-lock brake system (ABS)
Your vehicle is equipped with an anti-lock braking system (ABS). This
system helps you maintain steering control during emergency stops by
keeping the brakes from locking. Noise from the ABS pump ...
