2003 Chevrolet Tahoe knock sensors/harness

I have been having problems with my knock sensor engine light coming on, so I got the car scanned at the chevy dealer they said there was moisture inside of the computer of the car, so they tried to do an up grade on my cars computor and the power went out. The car wouldn't take another upload, it was frozen so I was told I needed a new computer ok I got it, so I thought this would take care of the problem. No sure didn't the knock sensors engine light came back on again so I had a guy replace the two knock sensors and the harness. The engine light came on again.I was just wondering if the information you gave the other person with the same problem as me resolved there problem.