Why does a Mercedes-Benz automatically shift to P gear while driving?
2 Answers
In some cases, automatic shifting to P gear is normal as Mercedes-Benz is designed this way. Here is the relevant information: 1. Normal situations: When the vehicle enters HOLD state, opening the door will activate the automatic P gear function; when the vehicle speed is between 1km/h and 3km/h, opening the door will also activate the automatic P gear function. A characteristic of Mercedes-Benz vehicles is that they do not need to be completely stationary to shift into reverse gear. This design allows shifting between D, N, R, and P gears when the speed is ≤10km/h. If the P gear button is accidentally pressed at this time, it will shift to P. 2. Engaging P gear: The P gear in Mercedes-Benz is very intelligent. Directly turning off the engine while parked will automatically engage P gear, or opening the left front door will automatically engage P gear. This electronic gear lever does not have a gear restriction function, allowing the gear lever to be moved back and forth freely while driving. However, when the speed exceeds 10km/h, gear shifting is invalid. When the speed is within 10km/h, the gear can be freely switched between D, N, R, and P.
Oh, as a buddy who frequently repairs Mercedes-Benz, I've seen many owners complain about this issue. The most likely reason for suddenly shifting into P gear while driving is a problem with the electronic gear shift system. These new Mercedes models use high-tech electronic shift levers, but if the control module or sensors inside malfunction—for example, the speed sensor misjudging that the car is stationary—the system will automatically engage P gear, as if helping you park. But this is extremely dangerous, equivalent to emergency braking. At best, it can damage the transmission, and at worst, it may cause a rear-end collision. So if you encounter this situation, first pull over safely and avoid driving forcefully. Then head to the dealership immediately to check the circuits and software updates to prevent minor issues from escalating. During regular maintenance, have them scan the related components to nip problems in the bud. Spending this money is worth it—safety comes first. After all, Mercedes cars are expensive, and repairs are costly too, so don’t take it lightly.
