Mercedes Benz

The fault code P179D indicates that the redundancy system for DIRECT SELECT was activated. This typically indicates a fault in the vehicle's transmission system. The redundancy system for DIRECT SELECT is a safety feature that is designed to prevent the transmission from engaging a gear that could cause damage to the engine or transmission. When this system is activated, the vehicle may not be able to shift into certain gears or may be limited to a specific gear range. To address this issue, you should take your vehicle to a certified mechanic or dealership for diagnosis and repair. Some possible causes of this fault code include: Faulty transmission control module (TCM): The TCM is responsible for controlling the transmission and may be faulty, preventing it from sending the correct signals to the transmission. Faulty transmission range sensor: The range sensor is responsible for sending the correct gear position information to the TCM. If the range sensor is faulty,...