Check the face of the sensors for damage to the lens. If the lenses are trashed, the truck is reporting the error as damaged sensors.
Next check the wiring behind the bumper. The wiring harness plugs into the sensor from the back of the bumper. The sensor releases from the back side as well ( the lens stays in the bumper ).
The common problem is the harness for the parking aid is damaged or corroded, once I get back by my shop manuals, I will see if the 10 beeps means anything ( don't know if that is an error code or if it is self test complete ).