You must first verify that no other parts or wires are connected to the APP sensor signal circuits. You will then need to run a system check on the vehicle. If after the check is done, you have any diagnostic codes you can simply replace the part the code is displaying as a failed or defective part. If after the system check is performed and no diagnostic codes are pulled up, you will need to locate the body harness connector that is linked to the instrument panel. Once located, inspect the connector for water leakage into the wires and pins. If there is a water leak you will need to repair the connector so the damaged area is covered. If no water is found, you must verify there is no debris or corrosion on the connector. If debris or corrosion is found, clean the connector as best as possible and reinstall it onto the vehicle.