Knock sensor harness check

You need to remove the intake manifold to inspect the harness. On the V6 engine, rodents love to eat the harness that the updated pigtail harness would have something like chili pepper sprayed on the insulation to stop them from eating it.

The 4 cylinder you really don't see that so most likely the knock sensor is defective. Had to replace the sensor on my sisters Honda for the knock sensor code. Once the intake is off you will have a better view.