If restarting the engine doesn't work, reset the transmission adoption values following the procedure below.
Turn the engine off.
Turn the key to position II. All dashboard lights will turn on, but the engine should stay off. You can accomplish this by pressing the start button twice without pressing the brake pedal.
Press the accelerator (throttle) pedal all the way to the floor to activate the kick-down switch.
Hold the throttle pedal pressed down for 30 seconds.
Take your foot off the throttle pedal and turn off the ignition by pressing the start/stop button one time.
Wait for ten seconds, then restart the engine.
If the transmission malfunction error message returns have the vehicle diagnosed as soon as possible. Do not continue to drive with the transmission malfunction light on.
Mercedes-Benz constantly provides software updates to fix problems that cause the Transmission Malfunction Stop problem. If resetting the transmission doesn't fix the problem, call the dealer to check if a software update is available for your transmission.
The next step in the troubleshooting process is to read the fault codes from the transmission control module. Reading the codes from the transition module is very easy, and you can perform it yourself at home. Follow this guide to learn how to read Mercedes-Benz fault codes.