Originally Posted by Matt L

If the battery is charged and the RCL works, you can indeed unlock the doors by turning the trunk lock cylinder.

However, what if the RCL fails? For example, say that you left your car outside during a huge rainstorm and water filled the area below the back seat, shorting out the RCL. How are you to get into the car? The trunk cylinder is not going to open the doors in this case.