I just had an interesting experience with our LG washing machine today. I found some hints for the solution online buried in some user forums, but I thought posting my particular solution here in a less cluttered blog might make it easier to find.
I had just run a load of laundry, emptied the machine, and reloaded. I put the detergent in and started the machine. After sitting for about 2 minutes with no activity, a "LE" error message appeared.
While the online forums indicated this might be a problem with a sensor, I was able to solve the problem by doing the following:
1. Press the Power button
2. Manually rotate the hopper 4 times clockwise and 4 times counter-clockwise.
3. Press the power button and run the machine normally.
Don't know if this will work for everyone, but it worked for me. If I keep getting the error message, I'll have to call LG and find out about this sensor I was reading about.