What causes the rear tires to lock up

"paulbelansky.91 , You did not state your year so I will post what info. I think may help in repair. Possible park brake stuck and may need replaced. You can check for voltage at the brake when you try to drive, and if it has voltage, the brake is defective. There is some info at last link also mentioning faulty brake solenoids. 1st link is a Video shows replacement of park brake. 2nd and 3rd links are forums that discuss your issue. 4th link is your service repair manual. Good luck. I hope this helped you out, if so let me know by pressing the helpful button.

https://www.youtube.com/watch?v=CQnVFKit...

http://www.doityourself.com/forum/motorc...

http://www.justanswer.com/electric-vehic...

https://www.manualslib.com/manual/836546..."