In the BMW 3 E46, when the rear transmission is turned on, long continuous signal is heard

In the BMW 3 E46 vehicles equipped with a PDC (Parking Assist System), in the exhaust pipe area, the transaction leading to the left sensor of the parktronic is often corroded, resulting in a failure of the system. This is a design shortcoming of this model, and in this situation we need to open the transaction with the help of the soldering-iron and the foller to restore contacts.