It may not be the USB port that is the problem.
There are two fuses that need to be checked as well.
Here's an image showing the location of the fuses on the motherboard, close to the USB port. They are both 1A fuses.
Use a DMM's (digital multimeter) Ohmmeter function to check if they are both OK.
You can also use the DMM's Voltmeter function to prove that the charge port is OK by connecting the charger to the device and then measuring the voltage on the output pins of the USB port connector.
(click on image)