On the day of the model recall, the new model was introduced, and the "unfavorable" Mercedes-Benz EQC was once again pushed to the cusp.
On February 18, the State Administration for Market Regulation issued a recall announcement recalling some EQC electric vehicles with production dates from November 30, 2018 to December 15, 2021, totaling 10,104 vehicles.
As for the reason for the recall, it is due to the deviation of the electric module in the EQC, and the lack of sealing problems in the cooling system in the electric drive module, resulting in the leakage of coolant, which in the long run will penetrate into the motor and even cause the vehicle to fail to start. Under extreme conditions, the output power of the vehicle's electric drive module will be reduced, and there is a safety hazard.
Public data show that since the end of 2019, Mercedes-Benz EQC sales in 2020 is 3863 vehicles, 2021 sales of 6098 vehicles, sales in China nearly 10,000 vehicles, the recall can be regarded as involving all models produced in China.
Coincidentally, a joint statement from a 68-bit Mercedes-Benz EQC owner at the beginning of the year also pointed out that EQC was suspected of high-volume motor failure.
Most of the owners of motor failures said that they were 1-2 months before the motor failure, and the words "fill coolant" were prompted on the central control screen after the vehicle was started, and the vehicle coolant was significantly reduced. Due to the lack of relevant experience and processing capacity, the 4S shop will uniformly choose to fill the coolant for this problem, and the coolant will continue to penetrate the motor, resulting in the vehicle can not start, and the central control screen prompts the word "fault".
There are also car owners who said that in the year and a half of his car purchase, there have been two motor failures, the first time the vehicle lost power, can not shift gears, go to the 4S shop to replace the front motor less than half a year, the motor has failed again, and need to replace the front and rear two motors. The motor is shipped to Germany for each repair, with a cycle of 45 days.
In addition to the joint statement of car owners, there are also many complaints about EQC motor problems on the car quality complaint platform. According to the public information of the car quality network, in 2021 alone, there are 20 complaints about Mercedes-Benz EQC, of which 19 are related to motor failures. Mercedes-Benz said that the EQC motor failure belongs to the manufacturer's "manufacturing deviation", not the "design defect" mentioned in the owner's complaint.
In fact, the issues related to cooling systems need to be considered in the long run. Usually, the core system of electric vehicles (three-electric system) includes batteries, motors, and electronic controls, in which the motor is the power source of electric vehicles, similar to the engines on traditional fuel vehicles.
At present, in order to make the vehicle more efficient, car companies mainly take improving the efficiency of the electric drive system as a preference, and the development of the electric drive system can be decomposed into motor design, inverter design and overall thermal management design.
From the perspective of technical routes, car companies represented by Japanese Toyota (hybrid vehicles) and American Tesla are more inclined to electric motor oil cooling technology, and European manufacturers represented by BBA are more inclined to use electric motor water cooling technology. Although the electric motor water cooling technology is difficult, the benefits are still considerable, not only allowing the motor to maintain a high continuous power output without derating, because the temperature reduction in the rotor also improves the durability of the entire drive system.
Since the technical threshold lies in the water seal, the manufacturing process needs to be closely followed up and the car company needs to iteratively analyze and control the overall failure rate for a long time, EQC as the first generation of Mercedes-Benz electric vehicles also need to accumulate relevant experience with the partner ZF through a long period of technical iteration.
It can be seen that the cooling system sealing problem is not a short-term solution, on the day of the EQC recall, Beijing Benz 2022 EQC 350 4MATIC new special edition was officially listed, compared with the ordinary version of the new car to upgrade the AMG sports kit and the standard 360 ° panoramic imaging system and blind spot auxiliary system and other safety configurations, this recall involves motor coolant leakage problems have not been improved in the new model.
While recalling and pushing new, quality control problems have also become a stumbling block hindering the pace of Mercedes-Benz electrification.
Turning over the recall data in the past three years, the number of recalls and the number of models of Mercedes-Benz in China have been high. In 2019, due to the "front shock absorber defect", Mercedes-Benz recalled the domestic E-class, C-class 571,000 vehicles, the number of recalls ranked first in China; in 2020, because of the oil leakage problem of the high-pressure fuel pump, Mercedes-Benz (China) Automobile Sales Co., Ltd. filed a total of 14 recall information with the State Administration for Market Regulation, plus 7 recall information filed by Beijing Benz Automobile Co., Ltd., the two totaled 21 recalls, ranking first in the list of car recalls; in 2021, Mercedes-Benz accumulated 17 recalls, a total of 2781204 vehicles, ranking first in the number of recalls again. Among them, due to the problem of communication module software design defects, Mercedes-Benz recalled related imported and domestic models covering almost the entire car series, totaling more than 2.6 million vehicles.
According to Duan Jianjun, chief operating officer of Beijing Benz sales and marketing, in 2022, Mercedes-Benz's "proportion of new energy model sales will continue to expand", but the first electric vehicle EQC is unfavorable in terms of sales and quality control, such as not improving quality problems in time, attaching importance to customer feedback, the pace of electrification has been significantly lagging behind the new forces and some traditional brands of Mercedes-Benz, undoubtedly on the road of "chronic suicide".