Hi. Does anyone know how to install remote start on 2001 bmw 520i? Full wiring description will be much appriciated.

Here's how I would do it:

. Remove the "S" connector from the starter solenoid terminal. Ensure the connection is clean and secure.

. Connect the black wire of the remote starter switch to the exposed "S" terminal.

. Connect the red wire of the remote starter switch to the Positive (+) battery terminal.

The solenoid should engage and the starter motor should operate.