E08 means that the throttle isn't in the zero position when you switch on the LCD, but it might also come if your throttle signal is out of range (less than 1v or greater than 4v). I'm pretty sure that E07 is a motor hall sensor fault. I would guess that the causes are related and probably due to an intermittent problem on your 5v rail somewhere. Unfortunately, the PAS, hall sensors, throttle, brakes and controller all use the 5v, so you have to check everywhere to find the fault. It could be a zip-tie pulled too tight, water in a connector, damaged wire or something like that.
It's easier to find faults when you have a total failure. Intermittent problems are very difficult to solve because everything is working when you do tests. A couple of times, people brought their bikes with intermittent faults to me to fix, but after a quick check and a ride around the block, I had to tell them to take it away and bring it back when it didn't work.
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