Think I finally got my ABS fixed so off to next project. Just tried the rear wiper on this car (that was given to me) for first time and it don’t work. Just curious if there is any common problems with them before I go after motor. When ignition is turned on I can hear hum coming from back there, think from lift gate unless fuel pump makes that type of noise. Reason I think it’s wiper is because it make same noise when I hit the rear wiper switch, hum last about 4-5 seconds. If anyone could point me in the right direction I would appreciate it. Thank you.