The first thing to check is the power supply.
First, check to make sure there are no blown fuses related to the rear lift gate. The first three pics are specific to fuse allocation and location. The fuse box is in the rear of the vehicle. I highlighted the fuses that need checked and the third picture shows location.
Here are a few links you may find helpful:
Let me know what you find or if you have other questions. Also, let me know if this happened all at once and if there are any other components with issues.
Images (Click to enlarge)
Wednesday, November 13th, 2019 AT 7:08 PM