Mercedes-Benz EQS 450+ V297

The MBUX Hyperscreen consists of three displays under a single glass panel, controlled by over 100 electronic control units. Owners frequently report the system becoming unresponsive, refreshing only every half second instead of smoothly, or restarting entirely while driving. This affects navigation, climate control, and vehicle settings. A recall affected 8,530 EQS and S-Class vehicles built between July 2020 and January 2022 for MBUX issues. Most software-related problems are resolved by dealer updates (3-23 hours depending on scope), and 2024+ cars with updated software show significant improvement. However, if the issue persists after updates, the central MBUX control unit may need hardware replacement, which costs €1,500-2,500 at a Mercedes dealer. The problem is most common on 2022 and early 2023 production cars.

This is the most widely reported safety concern. NHTSA data shows 72% of 2022 EQS complaints relate to forward collision avoidance and phantom braking. Owners report sudden, violent emergency braking at speeds above 70 km/h with nothing ahead, and abrupt braking while reversing in parking areas. In one documented case, the emergency brakes engaged at 90 km/h, deploying airbags and bringing the car to a halt for no reason. Mercedes has stated this falls under normal system operation and has not issued a specific recall for this issue. Some owners have switched the setting from 'normal' to 'late' or disabled it entirely, though it re-enables at each startup. The issue appears less frequent on 2024+ models with updated sensor calibration. While the braking itself is free, any resulting collision damage from a rear-end accident can be costly.

The EQS uses Mercedes AIRMATIC air suspension on all four corners. Common failure modes include leaking air struts (rubber seals become brittle over time, causing hissing and uneven ride height), compressor failure from moisture ingress, and faulty height sensors. A single air spring replacement costs €1,500-2,000 including labor. The compressor runs €1,000-1,500. If multiple components fail simultaneously (common as moisture from a failed compressor spreads to air springs), costs can reach €4,000-5,000. AIRMATIC components typically last 8-12 years or 100,000-150,000 km, so early EQS cars may not yet show these issues. However, as the car ages, this becomes the single most expensive potential repair. Damping valves are a separate potential failure at €700-1,200 each.

Multiple owners report significant range reduction after software updates at Mercedes dealers. One 2022 EQS 450+ owner saw range at 80% charge drop from 550 km to 450 km over 30 days post-update. Another reported full battery capacity dropped by 100 km after a dealer update. Mercedes recalled 14,912 EVs (2023-2025 EQS/EQE models) for battery management system software that did not meet production specifications. The fix requires a dealer visit and cannot be done over-the-air. Some owners have experienced cars locking them out after failed OTA updates. While the updates themselves are free, repeated dealer visits for diagnosis and correction consume time. In rare cases where the battery management software causes accelerated cell degradation, the 10-year battery warranty would apply.

The EQS has three 12V batteries: a 1.2 Ah auxiliary battery, a 26 Ah buffer battery, and a 60 Ah main battery. With over 100 control units drawing standby power, the 12V system can drain completely within one to two weeks of inactivity if the car is not plugged in. This leaves you unable to unlock or start the vehicle. Replacement of the main 12V battery costs €400-600 including programming into the SAM module. The issue is considered normal behavior for a car with this level of electronic complexity rather than a defect. A software update improved the 12V charging management on some models. Prevention is straightforward: keep the car plugged in when parked for extended periods, or use a battery tender on the 12V system.

Some EQS owners report the car stopping AC charging mid-session, showing 'charging start error' at public chargers, or DC fast charging speed dropping dramatically. Causes include a faulty temperature sensor on the charging unit that incorrectly detects overheating, on-board charger (AC/DC converter) malfunction, or communication errors between the car and charging infrastructure. In documented cases, the AC/DC converter required replacement after the high-voltage system was deactivated for diagnosis. Parts and labor for the on-board charger module run €1,200-2,500. A faulty temperature sensor is a cheaper fix at €300-500. Some charging issues are software-related and resolved by updates. Peak DC charging rate is 200 kW, allowing 10-80% in about 31 minutes when functioning correctly.

The EQS features Digital Light headlights with 1.3 million micro-mirrors per unit, creating incredibly precise adaptive beam patterns. When these fail, replacement costs are among the highest of any single component on the car. A standard Mercedes LED headlight already costs €1,500+ per unit; the Digital Light system with micro-mirror technology runs €2,500-4,000 per headlight including coding and labor. Current EQS headlights use a bonded, non-serviceable design where the lens cannot be replaced independently. Failure is rare but has been reported on forum posts, typically as condensation buildup followed by partial or complete malfunction. Within warranty, this is covered. Outside warranty, it represents one of the most expensive single-item repairs.

The EQS uses a complex thermal management system with multiple cooling loops for the battery, inverter, motor, and cabin. The expansion valve (part Y140/1) is electrically actuated and prone to mechanical sticking over time, causing battery overheating warnings and power reduction. Mercedes has issued an updated part number with improved reliability. The coolant switchover valve can also stick, generating cooling system alerts. Repair costs range from €500-800 for the expansion valve to €600-1,000 for a coolant pump. The heat pump system can also develop faults. Unlike the EQA/EQB/EQC models which had a widespread motor coolant leak recall, the EQS uses different motor sealing and has not been subject to the same issue. Most thermal management faults appear within the warranty period.