DIY tail light

i just got another question is....  when the car running forward. the ESC will give out over 100A to the motor. will it burn the diode?

yes 100A  is huge...  I never test the ESC. But it is from ESC spec.
you can have a look. even the cheap TBK-101 ESC has 60A output.
MSC230  has 160A. so if they are real, it is hard to use normal multi-meter to check it.