The electrical connector at the automatic transmission may leak fluid. Over time leaking fluid could migrate through the wiring harness and damage the transmission control module. If that happens a new harness and control module may be necessary to correct the problem.
Car Problem Reports
Mercedes-Benz S500 Wire Connector on Transmission May Leak Fluid and Damage Control Module
Mercedes-Benz S500 Problem
Average Mileage: 86,000 mi (54,000 mi - 118,000 mi)