Solution:  Turn off power for several seconds.  Turn the power back on while holding both edit keys (Edit Keys are the + and - keys above the on/off switch) along with holding both Throttle ( ALT) keys (Throttle alt keys are the top and bottom arrows on the left side of the radio) at the same time for several seconds.  After "FRT" appears on the digital screen,  release all four keys / buttons and press the "SEL" button.  An " OK " reading should appear on the digital screen.  Lastly, restart the radio and the ER1 message should be cleared.