2001 Mercedes Benz 320e auto gearbox does not change up whe

What you may be experiencing is your shift gate solenoid, which is the solenoid connected to the shift module that controls gear selection, beginning to fail. When this occurs on this model you will begin to have times where you cannot shift through or into specifc gears, you may not even be able to move out of park. When this occurs again there is one way of checking if this is the component that is failing. With you pulling the gear selector with one hand hit the top of the selector hard with the other hand, or a book, or something solid that won't damage the shift knob. If it pops loose, then this is your problem. If it doesn't pop loose it could still be the solenoid. They are sometimes extremely difficult to pop loose. Other issues that occur with the Shift Gate Module are electrical hard faults within the unit that require replacement for correction.