Mercedes-Benz S55 AMG transmission issue preventing shift to park and starting the engine on Mercedes-Benz S55 AMG

Some Mercedes-Benz S55 AMG owners report experiencing transmission issues that prevent shifting to Park and starting the engine. These problems may stem from a defective shifter module or brake light switch, which can hinder the ability to shift out of Park. Additionally, a faulty shifter selector module, potentially caused by a broken plastic shifter or spills on the center console, could be the culprit. In cases where the automatic transmission gear selector is stuck, owners can utilize the gear lever override feature to manually shift from Park to Drive. Furthermore, some owners have encountered issues related to the Locking Pawl, which may require replacement with a more durable aluminum part due to the original plastic version being prone to breaking. Troubleshooting often involves checking the brake light switch, as the shifter will not move out of Park without the brakes being engaged. It is crucial for owners to accurately diagnose the underlying issue to ensure smooth operation and prevent the transmission from entering Limp Mode, where it operates in 2nd gear.