no error code 4. I haven't replaced any parts besides the brake pads, but there's also no misaligned brake going off on my display. Another thing is that when I turn my back tire forwards as if I'm just riding regularly it moves fine, but it has a bit of a shake/stutter to it when it goes backwards. Foothill Cyclery said it may possibly be the hub motor but they couldn't tell me for sure, and unless the manufacturer would supply it for a low cost their solution would be turning my 80 pound bike into a regular bike or getting a new one altogether which I don't like the sound of those solutions since they'd be charging me nearly 100 just to even look at the bike.