99 olds bravada rear wiper not working

Check for power to your rear wiper motor. To do this you will have to remove the rear door trim. Once the door trim is removed check for power at your connector plug on the rear wiper motor with switch on. If there is power there than replace motor if not then start by checking fuses (which is a good idea to do before removing door panel because it's the easiest thing to check), connectors and wiring for damage and open circuit( cuts or broken pins in connectors or open/broken wiring)