Beep with a display saying EFO

Dear novscorp,
According to the error code chart (a loose insert included with the operating instructions) EF0 means two things: Error 1. Over sudsing  or  Error 2. Hot water does not enter.
For over sudsing, it lists the possible causes as: a high efficiency detergent was not used (the detergent brand will have "he" on it for high efficiency) or too much detergent was added.  The solution lists: Use only a high efficiency detergent.  Follow manufacturer's recommendation for dosage.  Amount may need to be adjusted for water temperature, water hardness, load size and soil level.  
For the 2nd error, hot water does not enter, it lists the possible causes as hot water hose is connected to the wrong faucet or hot water faucet is not turned on.  The solution lists: Connect hot water hose to hot water faucet and hot inlet on washer.  Be sure hot water facet is fully opened.
On a personal note, I received the same error when I mixed my detergent directly in with my color safe bleach.  It just caused a lot of suds in the machine.  One rinse cycle solved it.
Hope this helps, Ellenk4