Method for adding engine start-stop function to vehicle after production

The invention brings forward a method for adding an engine start-stop function to a vehicle after production. The vehicle comprises an engine controller ECU with a LIN communication interface and a vehicle body controller with the LIN communication interface. The method comprises following steps: adding a battery sensor to a storage battery of the vehicle and adding an LIN communicating line from the battery sensor to the vehicle body controller; replacing an electric generator with an electric generator having the LIN communicating function and using the replaced electric generator and the LIN communicating line of an engine controller ECU; adding an engine start-stop functional switch on a control interface of an instrument board of the vehicle; and renewing software of the engine controller ECU and the vehicle body controller. Parts for calibrated part and optional configuration of the software of the engine controller ECU are renewed. The part for optional configuration of the vehicle body controller is just renewed. Therefore, the vehicle can fulfill the engine start-stop function.