How do you reset b3 service indicator on glk 350?

To reset the B3 service indicator on a Mercedes-Benz GLK 350, turn the ignition to the "ON" position without starting the engine. Press the gas pedal three times within a few seconds, then turn the ignition off. After that, turn the ignition back on to check if the service indicator has been reset. If it hasn’t, repeat the process or consult the owner's manual for specific instructions.