My Book Studio Edition (1TB Ext HD) Error Code WHD16-IGG

My Dell PC runs a PC-Tools Hardware Check. It says that the “Targeted Read Failed” on the My Book attached via USB. What does this mean? The My Book appears to work fine, but is this a sign of impending failure? The text from the Dell Test report is below. Thanks!

SMART Short Self Test
Test Started 2/13/2014 12:48:21 PM
Error Message: The device reported the following status: The previous self-test completed having the read element of the test failed. 2/13/2014 12:48:32 PM
Error Message: The first failing LBA value is 977711947 and the failure occurred after the device had been operating for 20324 power-on hours. 2/13/2014 12:48:32 PM
Test Finished: Failed (Error code: WHD16-IGG)

Hello,

Try running a diagnostic using Western Digital’s DLG and post the results.