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1. Check whether the battery is powered on. Check the battery power according to the battery power.

a. If the battery is powered, please use a battery voltmeter or a multimeter to test the battery voltage. The voltage of a full battery is 54.6.

b. If the battery cannot be charged or the battery power cannot be displayed, it is a battery problem and needs to be replaced. If it is determined to be a battery problem, you do not need to check the following steps.

2. Remove the cable from the display screen and check whether the needle at the end of the cable is deformed.

3. Check whether the cables of the controller fall off.

Please first adjust the brake line on the disc brake to loosen the screw, adjust the brake line to test the brake function.

1. If you twist the throttle handle, the motor cannot work normally. Turn to the pedal, the motor works normally, it is the throttle handle failure.

2. If you twist the throttle handle, the motor will work normally. If the pedal is rotated and the motor does not work, the PAS sensor is faulty.

3. If you twist the throttle handle and turn the pedal, the throttle does not work. Remove and install the motor line again. If it can not be solved, it is to replace the motor.

This is how the S8 discharges speed:

1. Press and hold the left brake for 10 seconds before starting, and release the brake after 10 seconds.

2. Open the bolt motor switch and set PAS1 to PAS5.

A:1. Press the power button to start the bike.

2. Press + and - for 3 seconds at the same time to enter the parameter setting. Press M to set parameters to P08 and + to set numbers to 80-100. Press + and - to save.

Set PAS1 to 5 to achieve the release speed.

Please charge the battery more than 10+. Press the power button to start, press the M key to POW, we need to check the battery voltage. The voltage of a fully charged battery is shown at 54.6V. Please send me a photo of the display for confirmation.