2017 Mercedes-Benz B 250E: engine overheating

Filed Dec 15, 2025 · Electrical, Fuel system · AZ

In November 2024, the vehicle indicated "add coolant". The vehicle was brought to Mercedes Benz of Scottsdale for servicing. The dealership apparently added coolant without advising me that the B250-E has a 100% chance of failure to the Drive Unit / coolant intrusion unless a small part is replaced before coolant leaks into the inverter/entire engine. A few weeks later - the vehicle, while traveling on a highway, had a complete failure and essentially shutdown on moment's notice. It nearly caused a severe accident. Mercedes Benz USA and the MB Scottsdale dealership have refused to cover the cost of a repair (near $7,000) or replace the vehicle (that is completely inoperable). I was disturbed to learn that a failure rate to the Large Drive Module is ONE HUNDRED PERCENT. This same problem exists for early Toyota RAV4 EVs and some Teslas. I encourage you to go to [XXX] to confirm the facts. These vehicles should be recalled. Consumers like me should not have to shoulder the expense due a defect that the manufacturer should cover/resolve. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Nov 1, 2023 · Electrical, Engine · CA

My car just stalled and was not able to move on the highway exit which caused a high risk for the safety of passengers and the safety of others. The car has been towed to a Mercedes Dealer in West Covina, California. and they indicate that the coolant leaked into the drive motor and caused the car to stop. Prior to this car stall, there was no warning lamp, messages, or other symptoms of the problem prior to the failure. After the car stalls on the street, a failure message appeared asking to send the car to the shop.

Filed Jan 17, 2023 · Transmission · WA

Electric motor has a coolant line running through it that has developed a leak and is in the process of destroying the motor. This is apparently a known issue that affects all Mercedes E-Class Electric Drive, B250e, Toyota RAV4-EV and some early Tesla Model S cars that have this early type Tesla motor installed. If the motor is not replaced, it could seize. Our car has only 23K miles on it but is out of warranty. I checked the speed sensor on 1/16 and found lots of coolant leakage and evidence of motor abrasion (see attached picture). The car developed a whining/whirring sound a couple of months earlier that are indicative of the problem.

Filed Jan 5, 2023 · Engine · MA

I needed a new electric motor. It was covered by the warranty but would not be if it fails again, and it's known to happen again. This is a very common issue with the Mercedes B250E from 2014-2017. I believe this should be a recall. The cost to consumers for repair is around $20,000. There is a problem with coolant leaking into the electric motor causing it to fail. see all the other owners on these facebook groups having the same issue: https://www.facebook.com/groups/795845034211580 and https://www.facebook.com/groups/205091799685747

Filed Dec 11, 2022 · Electrical · CA

Mercedes dealer indicated a coolant leak resulted in an electrical failure and required that I pay $18,000 to replace the motor system. This is a known issue, however. When I mentioned that this is a manufacturing defect affecting numerous b250e I was referred to Mercedes Benz USA. Mercedes Benz USA offered a $1000 discount towards repairs rather than waiving the cost entirely. There are no details or tools available by mercedes or others to diagnose and resolve this issue. I would like this vehicle recalled. I want to be refunded the entire amount of the vehicle or at least the amortized value at the time of the incident.

Filed Oct 23, 2022 · Engine, Transmission · WA

The electric motor is destined to fail because of a coolant leak at the speed sensor. According to many accounts the motor will fail and lock up the system. My car has not yet failed but I fear an accident will happen depending on where it falls. My extended warranty from Endurance is no help as they denied coverage for the motor. I have no alternative transportation and am out $17000 on the car.

Filed Jun 10, 2022 · Fuel system, Transmission · TN

the electric motor has suffered a coolant leak. this is a known issue in the Mercedes B250e, Rav4 EV, and Tesla Model S. This issue should be recalled and repaired.

Filed Jun 3, 2022 · Engine · UT

Coolant leaked into drive unit causing total failure. This is a known issue and should be subject to a recall of these cars. As a dealer we’ve had repeated issues with this.