AutoUtility currently tracks 7 official NHTSA owner defect complaints for the 2021 Mercedes-Benz GLB. Engine & Cooling issues are the most frequently reported category, appearing in 2 complaints (28.6% of submitted records). Zero crashes, fires, injury reports, or fatality reports are cited across these complaint records.
Factual proportion of owner complaints categorized by automotive subsystem in NHTSA records
2 owner complaints submitted to NHTSA ODI for this subsystem.
1 owner complaint submitted to NHTSA ODI for this subsystem.
1 owner complaint submitted to NHTSA ODI for this subsystem.
1 owner complaint submitted to NHTSA ODI for this subsystem.
Representative defect filings submitted by owners to the NHTSA Office of Defects Investigation
"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..."
"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..."
"The contact owns a 2021 Mercedes-Benz AMG GLB35. The contact stated that while reversing down the driveway at approximately 4 MPH, the contact turned the steering wheel to the left and the vehicle started losing motive power. The contact stated that the RPMs were extremely high and the vehicle..."
"On 4/13/25 while driving my car on the highway, along with my 2 young children, I began to hear what initally sounded like a "flapping" noise. I rolled the windows down and after a minute or 2 the sound got lounder. There was never a warning or any type of safety icon that appeared on the control..."
"The contact owned a 2021 Mercedes-Benz GLB35. The contact stated while driving at 35 MPH, the brake pedal was depressed; however, the vehicle failed to stop as intended. There was no warning light illuminated. The contact stated that neither the dealer nor an independent mechanic was contacted. The..."
Reported defect complaint volume across sibling model years (2020–2026)
| Model Year | NHTSA Complaints | Crash Reports | Safety Recalls | Detailed Report |
|---|---|---|---|---|
| 2020 Mercedes-Benz GLB | 57 | 2 | 20 | View 2020 Problems → |
| 2021 Mercedes-Benz GLB Current Page | 7 | 0 | 12 | Current |
| 2022 Mercedes-Benz GLB | 13 | 2 | 1 | View 2022 Problems → |
| 2023 Mercedes-Benz GLB | 12 | 0 | 1 | View 2023 Problems → |
| 2024 Mercedes-Benz GLB | 0 | 0 | 2 | View 2024 Problems → |
| 2025 Mercedes-Benz GLB | 0 | 0 | 2 | View 2025 Problems → |
| 2026 Mercedes-Benz GLB | 1 | 0 | 1 | View 2026 Problems → |
Complete distribution of consumer defect reports across all 7 granular NHTSA system and subsystem classifications
| Vehicle Component / System | Total Complaints | Crash Reports | Fire Reports | Injury Entries | Fatality Entries |
|---|---|---|---|---|---|
| ELECTRICAL SYSTEM,ENGINE | 1 | 0 | 0 | 0 | 0 |
| Engine NHTSA category: ENGINE | 1 | 0 | 0 | 0 | 0 |
| ENGINE,FUEL/PROPULSION SYSTEM | 1 | 0 | 0 | 0 | 0 |
| Service Brakes NHTSA category: SERVICE BRAKES, HYDRAULIC | 1 | 0 | 0 | 0 | 0 |
| SUSPENSION,POWER TRAIN | 1 | 0 | 0 | 0 | 0 |
| Visibility & Wipers NHTSA category: VISIBILITY/WIPER | 1 | 0 | 0 | 0 | 0 |
| Wheels & Hubs NHTSA category: WHEELS | 1 | 0 | 0 | 0 | 0 |
Cross-reference safety recalls, crash test safety ratings, and EPA fuel economy for this model year
Key performance indicators, EPA fuel economy specs, powertrain variants, and summary ratings.
Official recall campaigns, safety defect descriptions, and manufacturer free remedy instructions.
NHTSA 5-Star NCAP crash test results, driver assistance systems, and rollover resistance ratings.
EPA fuel economy ratings, electric range, and annual energy cost benchmarks.
Direct, deterministic answers synthesized from verified United States government databases for the 2021 Mercedes-Benz GLB
In official NHTSA consumer records, the most frequently cited issue area for the 2021 Mercedes-Benz GLB is Engine & Cooling, appearing in 2 records (28.6% of submitted filings).
Secondary reported categories include Fuel & Propulsion System (1) and Electrical System (1).
AutoUtility does not issue subjective reliability scores or commercial ratings. In official United States government records, NHTSA tracks 7 consumer defect complaints and 12 safety recall campaigns for the 2021 Mercedes-Benz GLB.
Reviewing documented component complaint distributions, recall remedy notices, and active federal investigations provides an objective, evidence-based view of the vehicle's historical safety and defect record.
Consumer complaint records on file with NHTSA for the 2021 Mercedes-Benz GLB cite zero crashes, zero fires, and zero injuries.
Incident entries represent consumer descriptions at the time of submission to federal authorities and do not establish mechanical causation or legal liability.
The complaint records on this page are retrieved directly from the NHTSA Office of Defects Investigation (ODI) public database under 49 CFR Part 576.
Local Production Store Compiled: August 2026 • Deterministic Audited Dataset • Zero Dynamic External API Runtime Latency.