Peugeot 308 Secret Menu -

To access the secret engineering or "Expert Mode" menu on a Peugeot 308 (typically models with the SMEG or NAC infotainment systems), you can follow these steps to reveal hidden diagnostic data and system settings.  How to Access the Hidden Menu 

The method for entering the secret menu depends entirely on which infotainment system your Peugeot 308 uses. For the Smeg and Smeg+ Systems (T9 Model 2013-2017) peugeot 308 secret menu

A hidden service menu will appear, displaying technical data. To access the secret engineering or "Expert Mode"

Here are the precise instructions to unlock it, depending on the generation of your vehicle: 🎵 The "Piano Key" Method (Gen 2 / SMEG & RCC Systems) Use the wiper stalk button to scroll to

1. Use the wiper stalk button to scroll to the "Personalization" menu.
2. Long-press the button for 5 seconds until "ENGINEER MODE" blinks.
3. Scroll to "Display: STD." Change it to "Display: FULL."