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If the knock sensors and harnesses have been replaced yet the code is still setting then the problem could either be in the wiring harness between the knock sensor harness and the ECM, or it could be in the ECM itself. A wiring problem would be much more likely. It could be a connection issue, open circuit, or short to power or ground or another circuit. The next step will be to test the knock sensor wiring, odds are there is a wiring problem.
P0745 is for the line pressure solenoid on the transmission valve body. This code can be caused by a bad solenoid, wiring issue, or the transmission control module. It's not likely to be the transmission control module but the wiring and solenoid should be tested, most solenoid circuit codes are caused by failed solenoids.