Automatic Transmission Floor Shift problems of the 2000 Mercedes Benz 320

Vehicle automatically shifted into lowest gear while driving, causing a dangerous condition, slowing the vehicle substantially in traffic. Vehicle refused to shift into higher gear or reverse. Towed to the dealership, who replaced shifter mechanism due to electronic failure, caused by spills. Observation of the part showed no residue from any liquid. Dealership said it happened all the time because the cup holder was right above the circuit board in the console and it was not sealed. Stated the replacement part installed was improved to prevent this from happening again.