2021 Mercedes-Benz GLB: problems, recalls and reliability
11 recalls and 29 owner complaints on record; most reports concern engine; the 2022 model year looks more trouble-free.
Data updated weekly · 1 new complaint in the last 90 days · latest recall Jul 2026
All counts are reports filed with NHTSA in the United States - US market only, not worldwide totals.
Common problems
Computed from 29 owner complaints filed with NHTSA for this exact model year.
“The contact owns a 2021 Mercedes-Benz GLB250. The contact stated that the front stationary roof panel detached from the vehicle and shattered. The vehicle was taken to the dealer but was not diagnosed or repaired. The contact became aware of a recall with a similar failure; however, the VIN was not included, and the model year was not included in a recall for the failure. The manufacturer was not made aware of the failure. The failure mileage was approximately 63,000.”Owner report · Visibility · Aug 2026
“Family and I were driving on the interstate and heard a loud bang (like a shotgun) followed by immediate glass everywhere. The panoramic sunroof exploded. We had to drive 4 hours like this - lucky we didn't jerk the wheel on the interstate with the noise. Absolutely sickening that this is so prevalent and Mercedes won't do anything about it.”Owner report · Unknown Or Other · Apr 2026
“I purchased this vehicle in May 28 2025. I certified car. I took in for oil change Nov 17-2025. Found out they had lot of issues., left front bushing arm leaking. Rt engine mount leaking. Bad brakes battery low. Bad tire rt back passage side.front wheel axle and rear wheel axle is bad and screw on the engine mount is missing. Screw and leaking..?and the vehicle needed a alignment.”Owner report · Wheels · Nov 2025
Show 7 more owner reports
“Jerking and loud noise from the engine after attempting to accelerate from a red light stop. Vehicle is idling very roughly and almost sounds like a diesel engine. Check engine light came on. Inspection at the dealership found multiple faults for camshaft positions deviating from the specified value. When the oil filter was removed, the shop reported finding some metal particles in the oil. The conclusion was that a mechanical fault caused a metal part in the engine to brake and clog up the engine. The car did not run smoothly after the jerking sound and could have caused an accident if the car was in active motion. The recommendation now is that the engine needs to be replaced.”Owner report · Unknown Or Other · May 2025
“While driving, the panoramic moonroof on my 2021 Mercedes-Benz GLB 250 (VIN: [XXX] ) suddenly shattered without any visible impact or prior damage. It sounded like an explosion, and glass rained down into the vehicle. This could have caused serious injury to myself or my child. There was no indication that a rock or debris hit the vehicle. No vehicles were in front of me, and I have no history of impact damage. This seems to have happened spontaneously, and after researching the issue, I found it is a common problem across various Mercedes-Benz models. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)”Owner report · Unknown Or Other · May 2025
“It appears as if there is an issue with the transmission. In this vehicle. When you come to a stop the transmission has a loud clunking noise coming from left side of vehicle. The clunking occurs when the vehicle downshifts. It clunks from d4 to d3, then d3 to d2 , and again at d2 to d1. I have taken it to the dealer numerous times to have it checked. The service mgr weny for s test drive with me and heard it. I was then told the clunking was " normal" . I purchased the vehicle as a certified used vehicle from the same dealer . This has been occuring since purchase in may 2024”Owner report · Power Train · May 2024
“Entire electrical system went out while driving causing check engine light to come on after the failure of system; there was no dashboard working at all when the system went out; without the dashboard out it was not certain if the vehicle was safe to drive anymore; the dealer has not been able to reproduce the problem; the vehicle has been with the dealer repair system for several weeks and have not been able to determine what happened; they have indicated that the vehicle had some type of water intrusion which short circuited the electrical system; the believes that the water entered into from the windshield area with a possible clogged water drain; there was no prior warning”Owner report · Air Bags · Oct 2023
“The contact owns a 2021 Mercedes-Benz GLB250. The contact stated that the vehicle was parked in the garage; however, after driving out of the garage, the contact became aware of a crack on the windshield from the rear-view mirror ten inches downward. The contact stated that the crack seemed to be on the inside over the sensors. The vehicle had not yet been diagnosed or repaired. The dealer nor manufacturer was notified of the failure. The failure mileage was 13,716.”Owner report · Visibility · Aug 2023
“My fuel tank cover would not open. Car was under warranty so MB was able to replace the motor of the fuel cap release. Problem, there is no manual release for the fuel cap so if you are low on fuel and need to fill up, you would be stranded. They need a manual release for the fuel cap for safety.”Owner report · Unknown Or Other · May 2023
“The car has 29,000 miles and I took it on a two day trip across part of the country. It was driven hard but had a oil change before leaving. After arriving home it started to sputter and have no "energy". I had the cabin filter and engine filter changed and another oil change just in case. took it to deal as it continued to sputter, even worse, jerk forward. It blew a cylinder head. Checking the internet I find that this is a usual problem with this year and model car. Why isn't it in the recall if a lot of this model has this problem?”Owner report · Unknown Or Other · May 2023
Recalls - 11 campaigns
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 GLB250 vehicles. The Electronic Stability Program (ESP) unit may be damaged, which can result in disabled anti-lock brakes (ABS), disabled electronic stability control (ESC), and an electrical short circuit.
Remedy: Dealers will replace the ESP unit, free of charge. Owner notification letters were mailed October 28, 2022. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2022090009.
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 GLB 250 and AMG GLB 35 vehicles. The driver-side window air bag may not have been mounted correctly to the lower area of the A-pillar. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 226, "Ejection Mitigation."
Remedy: Dealers will inspect the mounting of the driver-side window air bag and repair it as necessary, free of charge. Owner notification letters were mailed December 2021. Owners may contact MBUSA customer service at 1-800-367-6372.
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 GLB 250 vehicles. The level sensor linkage on the rear axle might not have been installed properly, which could affect the headlight leveling function. MBUSA's number for this recall is 2022050011.
Remedy: Dealers will inspect and repair the level sensor linkage, as necessary, free of charge. Owner notification letters were mailed June 10, 2022. Owners may contact MBUSA customer service at 1-800-367-6372.
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2022 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, AMG GT-Class, C-Class, E-Class, S-Class, SL-Class, GLC-Class, CLS-Class, GLB-Class, and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. An error in the communication module's SIM card software can cause a mobile network connection failure, disabling the emergency call (eCall) system.
Remedy: The communication module software will be updated through an Over-the-Air (OTA) update or by a dealer, free of charge. Owner notification letters were mailed July 8, 2022. Owner notification letters will be mailed in phases, on July 8, 2022, May 17, 2024, July 29, 2024, and September 27, 2024. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's numbers are for this recall is 2022060005 and 2023110006.
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2019-2021 CLA-Class, GLE/GLS-Class, A-Class, E-Class, E-Class Coupe and Convertible, GLA/GLB-Class, GLC-Class, CLS-Class, and AMG GT-Class 4-door Coupe vehicles. Please refer to MBUSA's recall report for specific vehicle model details. The MBUX multimedia system software may cause the display to remain black, or reboot after startup. This could result in the rearview camera image not displaying properly. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 111, "Rear Visibility."
Remedy: The multimedia system software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. Owner notification letters were mailed beginning June 28, 2021. Owners may contact MBUSA customer service at 1-800-367-6373. MBUSA's number for this recall is 2021050012.
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.
Remedy: Dealers will replace the driver's door lock, free of charge. Owner notification letters are expected to be mailed September 18, 2026. Owners may contact MBUSA customer service at 1-800-367-6372. Vehicle Identification Numbers (VINs) involved in this recall will be searchable on NHTSA.gov beginning July 31, 2026.
Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2021 GLB 250 vehicles. These vehicles may be equipped with an incorrect front driver's air bag module.
Remedy: Dealers will inspect and replace the front driver's air bag, as necessary, free of charge. Owner notification letters were mailed March 25, 2022. Owners may contact MBUSA customer service at 1-800-367-6372.
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2016 - 2021 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, GT-Class, C-Class, E-Class, S-Class, CLS-Class, SL-Class, B-Class, GLB-Class, GLC-Class, and G-Class vehicles. Please refer to the Part 573 report for specific vehicle model details. The software design of the communication module may fail to communicate the correct vehicle location for the emergency call system (eCall) in the event of a crash.
Remedy: MBUSA will notify owners, and the communication module software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. The recall began March 12, 2021. Owners may contact MBUSA customer service at 1-877-762-8267. MBUSA's number for this recall is 2021020025.
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2018-2021 CLA-Class, GLE/GLS-Class, A-Class, C-Class, E-Class, E-Class Coupe/Convertible, GLA/GLB-Class, GLC-Class, and CLS-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. The rearview camera may not display the rearview image due to a software error. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 111, "Rear Visibility."
Remedy: Dealers will update the rearview camera software, free of charge. Owner notification letters were mailed July 15, 2022. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2022060007.
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020-2021 GLB250 vehicles. The wheel arch covers on the front fenders might not have been installed correctly, allow them to detach.
Remedy: MBUSA will notify owners, and dealers will check the installation of the front wheel arch covers and correct them as necessary, free of charge. Owner letters were mailed May 21, 2021. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2021040015.
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 GLB35 AMG, and 2020-2021 GLB250 vehicles. The side spoilers on the tailgate might not have been installed correctly, allowing them to detach.
Remedy: MBUSA will notify owners, and dealers will inspect and, if necessary, replace the side spoilers, free of charge. Owner letters were mailed July 2, 2021. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2021050009.
How other years compare
Check your exact GLB by VIN
Recalls and equipment differ between individual vehicles. Decode your VIN to see what applies to yours.
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Is the 2021 Mercedes-Benz GLB reliable?
NHTSA has 29 owner complaints and 11 recall campaigns on record for the 2021 Mercedes-Benz GLB. The most complained-about area is engine.
Does the 2021 Mercedes-Benz GLB have open recalls?
11 recall campaigns have been issued, the latest concerning electronic stability control (esc):control module. Check your specific vehicle by VIN - recall repairs are free at franchised dealers.
Source: NHTSA recall campaigns and owner complaints (public domain). Counts reflect reports on file and are not a defect rate.