Our long-term Mercedes A 220 has recently presented some concerns regarding its transmission performance. Specifically, we’ve noticed increasingly rough and jerky shifts, detracting from the otherwise smooth driving experience expected from a Mercedes-Benz. This issue prompted a service visit to our local dealership to diagnose and hopefully rectify the problem.
The dealership service team diligently investigated the Mercedes A 220’s transmission behavior. According to the service report, technicians were able to replicate the reported rough shifting in 4 out of 8 attempts, across both Comfort and Sport driving modes. This occurred during 1-2 upshifts at speeds between 15-20 mph. The technicians noted “harsh clutch engagement and shift characteristics.” Diagnostic scans were performed using SDS (Star Diagnosis System) and a battery charger was connected to maintain optimal voltage during testing. A quick test was conducted, revealing no current or relevant fault codes related to the transmission issue. Furthermore, a check of Mercedes A 220’s DCT (Dual Clutch Transmission) fluid level, as recommended by the shop foreman, showed the fluid to be within specifications at dipstick marking 5 at 158 degrees Fahrenheit.
With no apparent mechanical faults identified and no relevant technical service bulletins (tips documents) found, the dealership proceeded with a “full basic transmission adaptations” procedure. This process aims to re-learn the transmission’s shift and wet clutch application characteristics. This adaptation was performed via the SDS system. Following the adaptation procedure, a quality control road test was conducted. The service report indicated a significant improvement, stating that the shift pattern and clutch application in both Comfort and Sport settings were improved by “99%” after the adaptations.
Upon collecting the Mercedes A 220, the service advisor detailed the performed services but seemed hesitant to confirm a definitive mechanical problem. Instead, the advisor attributed some of the driving characteristics to the inherent nature of a DCT. While DCT transmissions can sometimes exhibit minor jerkiness, we believe the severity experienced in our Mercedes A 220 was beyond normal operation, especially considering its initial smooth performance and the gradual degradation over mileage.
Despite the service advisor’s ambiguous explanation, the transmission adaptation service was performed at no charge. This raises questions about the perceived severity and nature of the issue. Nevertheless, the Mercedes A 220 is now back in our possession. The crucial next step is to conduct thorough real-world driving tests to evaluate whether these “fixes,” specifically the transmission adaptations, have effectively resolved the rough shifting problems. We will be putting the Mercedes A 220 through its paces in various driving conditions to determine if the transmission performance has truly returned to its expected smooth and refined operation. Stay tuned for our follow-up report on the effectiveness of this Mercedes-Benz service intervention and the long-term driving experience of our A 220.
