As I was driving down road car began to lose power, check engine light came on and car went into limp mode. Car was towed to nearest repair shop where analysis was made. I was advised to take to dealership for repair. Advised that there was a service campaign issued by the manufacturer on GLB class with M260 motors. See attached report. Took car to MB dealer and informed that an update to the ECU was needed but not available at this time. See attached report. Returned home to PA called Mercedes main office Customer service to check warranty and coverage yes it covered once dealer verifies codes. Called the federal safety agency to report where they verified that the manufacturer had agreed to repair the issue and extended the waranty instead of doing a recall. Was advised to file report online because the dealership is now demanding payment to do the software update. Which was already verified see attached. A rail pressure sensor is a core engine management component that measures fuel pressure in the fuel rail, sends real-time data to the engine computer, and helps regulate fuel delivery. Rail Pressure Sensor system Fault code P019185 Stores in MED41 control unit. Available for Inspection
The worst 2021 Mercedes-Benz GLB 250 4matic problems
Ranked by number of owner complaints. Mileage and cost come from what owners wrote.
- Engine2
- Electrical1
- Fuel system1
Problems by type
Tap a problem to see which part fails, at what mileage and in which other years.
- Engine2
- Electrical1
- Fuel system1
Recalls 1
Latches/locks/linkages: doors: lock
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020-2021 CLA, 2019-2022 A-Class, 2022-2023 C-Class, 2024 CLE, 2020-2026 GLA/GLB, and 2023-2024 GLC vehicles. Please refer to MBUSA's recall report for specific model information. The micro-switch in the driver's door lock may corrode and fail to detect an open door, preventing the electronic parking brake or "Auto-Park" feature from engaging automatically. This may result in a vehicle rollaway.
- Risk
- A vehicle rollaway increases the risk of a crash or injury.
- Remedy
- Dealers will replace the driver's door lock, free of charge. Owner notification letters are expected to be mailed September 18, 2026. This will be a phased campaign, with the remedy becoming available in different phases based on model and model years. Owners may contact MBUSA customer service at 1‑800‑367‑6372. Vehicle Identification Numbers (VINs) involved in this recall will be searchable on beginning July 31, 2026.
Recall number 26V481000 · Recall details
Technical service bulletins for the 2021 Mercedes-Benz GLB 250 4matic 60
Bulletins tell dealers how to fix known problems. A warranty extension means the manufacturer pays for that repair for longer.
- Dear Mercedes-Benz Owner: In our continuing efforts to ensure the proper performance of Mercedes-Benz...
- Fuel/propulsion system
- Slight creaking noises when steering
- Repeat workshop visit for vehicle vibration while braking from 60MPH. NOTE: Although the symptom is...
- Radio station cover art does not refresh when switching stations
- Clanking noise from the area of the speakers in the doors
- Temporary no start condition with check engine light and multiple warning messages
- Intermittent shift feel or thud/clunk noise perceived, such as a brief jerk or transmission reaction...
- Customers may report one or more of the following: • Transmission malfunction message • Check engine light...
- Tailgate opens unintentionally
See all 60 bulletins for the 2021 Mercedes-Benz GLB 250 4matic
What 2021 Mercedes-Benz GLB 250 4matic owners say
Most recent owner complaints, unedited.
While driving on the highway at 70mph my transmission malfunction warning light illuminated in red and my vehicle went into limp mode, creating a life threatening safety defect at highway speeds. I immediately took the vehicle to Mercedes Benz of Pittsburgh. The dealer's own diagnostic tech notes stated 'software is in preparation for concern' confirming this is a known safety defect on Mercedes' end. The dealer was unable to replicate the concern or produce stored fault codes but acknowledged software is actively being developed to address this issue. I contacted MBUSA who confirmed the only escalation path available is a buyback, meaning Mercedes cannot provide a timeline for the software fix. I am currently unable to safely drive my vehicle and am requesting this be investigated as a potential safety defect that may affect other 2021 Mercedes GLB 250 owners.
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Questions about the 2021 Mercedes-Benz GLB 250 4matic
Is the 2021 Mercedes-Benz GLB 250 4matic reliable?
Owners have filed 2 complaints about the 2021 Mercedes-Benz GLB 250 4matic, close to a typical GLB 250 4matic model year.
What is the most common problem with the 2021 Mercedes-Benz GLB 250 4matic?
Engine and cooling, with 2 complaints. Next is electrical (1).
How many recalls does the 2021 Mercedes-Benz GLB 250 4matic have?
1 recall, covering latches/locks/linkages.
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