What can car fitting and coding do for my vehicle? As explained above, most vehicles have market-specific settings for their features. Also, most vehicles have limitations and other restrictions. With the help of coding, a user can change the bells on their car, set how many times their one-touch signal flashes for one touch, remember Start / Stop systems settings and more. Encoders can also turn headlights on corners with fog lights, turn off some hums and enable multiple features of the comfort module.