daweidu

I just got glc 300 a few days ago. The acc is keep change the speed. There is one time I am driving on 25 limited road and it changed to 75. my god.

6G Schnell

Congrats on your new car!

Something is wrong here, cruise control should not go over the stored max speed.
Can you check what the max speed is set to?

Hint: When activating the cruise control, stored speed is shown in the multifunction display for five seconds.

daweidu

got it setting traffic signal and disable limited adaptive