Mercedes-Benz GLB known issues by generation

By CarWhere Research · Updated

The GLB (X247, 2020 on) has no well-documented recurring mechanical failure yet. Its notable issues are recalls on early 2020–2021 builds: front-axle carrier corrosion, water entering the front footwells, and the shared driver door-lock micro-switch campaign, plus an MBUX display software fix. 4 documented issues, 4 with NHTSA recall numbers.

CarWhere lists 4 documented GLB issues, including 4 NHTSA safety recalls, each with affected years, engines, symptoms, pre-purchase checks and a source.

GLB generations at a glance

Mercedes-Benz GLB chassis codes and the known issues listed for each
Chassis codeModel yearsIssues on this page
X2472020–present (X247 GLB)Front axle integral carrier may corrode and fail · Water may enter the front footwells and damage electronics · Driver door-lock micro-switch may corrode (rollaway risk) · MBUX display may stay black, affecting the rearview camera

X247 GLB problems (2020–present)

Front axle integral carrier may corrode and fail (2020–2021)

Safety recall
Chassis:
X247 (GLB 250, AMG GLB 35)
Years:
2020–2021
Engine:
All

About 38,000 2020 GLB 250, 2021 AMG GLB 35 and 2019–2020 A 220 vehicles were recalled because the integral carrier that supports the front axle could corrode and fail. A failed carrier affects front suspension geometry and can reduce vehicle control. Dealers inspect the carrier and replace it as needed. Buyers in road-salt regions should look closely at underbody corrosion around the front subframe. Recall repairs are free at any Mercedes-Benz dealer regardless of the vehicle's age or ownership history, and the NHTSA recall lookup shows whether the campaign is still open on a specific VIN.

Symptoms

  • Clunks from the front suspension
  • Wandering or uneven steering feel

Check before buying

  • Inspect the front subframe and carrier for corrosion
  • Confirm 21V-990 completion

NHTSA recall: 21V-990 (2021-12) · 38,312 vehicles

Sources: [3]

Water may enter the front footwells and damage electronics (2020)

Safety recall
Chassis:
X247 (GLB 250)
Years:
2020
Engine:
All

About 5,700 2020 GLB 250s were recalled because water could enter through the wheel-well area into the front occupant footwells. Water can damage electrical components there, which can blank the instrument cluster, stall the engine while driving or prevent starting. Dealers seal the body in the wheel-well area and inspect and repair any water damage. A damp carpet or musty smell is a red flag even if the recall has been completed.

Symptoms

  • Wet front carpet
  • Instrument cluster going blank
  • Stalling or no-start

Check before buying

  • Feel under the front floor mats for moisture
  • Confirm 21V-403 completion

NHTSA recall: 21V-403 (2021-05) · 5,680 vehicles

Sources: [2]

Driver door-lock micro-switch may corrode (rollaway risk) (2020–2026)

Safety recall
Chassis:
X247 (GLB 250, AMG GLB 35)
Years:
2020–2026
Engine:
All

The GLB is covered across 2020–2026 by a 2026 recall of about 311,000 vehicles. The driver's door-lock micro-switch can corrode and stop detecting an open door. The automatic parking brake or Auto-Park may then fail to engage when the driver exits, which creates a rollaway risk. Dealers replace the driver's door lock, with the remedy released in phases by model and year. Until it is repaired, drivers should set the parking brake and select Park deliberately.

Symptoms

  • No door-open warning
  • Parking brake not applying automatically on exit

Check before buying

  • Test the door-open warning with the engine running
  • Check 26V-481 status

NHTSA recall: 26V-481 (2026-07) · 310,667 vehicles

Sources: [4]

MBUX display may stay black, affecting the rearview camera (2020–2021)

Safety recall
Chassis:
X247 (GLB 250, AMG GLB 35)
Years:
2020–2021
Engine:
All

About 343,000 2019–2021 vehicles across many lines, including the GLB, were recalled because the MBUX multimedia software could leave the display black or reboot it after start-up. When that happens the rearview camera image may not appear, which fails the federal rear-visibility standard. The software is updated by a dealer or over the air. A camera that comes on reliably after several restarts suggests the update is in place, but confirm it by VIN.

Symptoms

  • Central display black after start
  • Display rebooting
  • No rearview camera image

Check before buying

  • Restart the vehicle several times and select Reverse each time
  • Confirm 21V-354 completion

NHTSA recall: 21V-354 (2021-05) · 343,191 vehicles

Sources: [1]

Related GLB research

This page explains specific mechanical issues and recalls. Which model years drew the most owner complaints is a different question, answered in the years-to-avoid research from NHTSA complaint and service-bulletin counts.

Confirm exactly how a GLB was built before you buy.

Engine, transmission and factory options decide which of these issues apply. The data card records how a Mercedes-Benz GLB was built — option codes, paint, upholstery and equipment; CarWhere decodes it from the VIN, free availability check, $9.99 only if build data exists for that car.

Mercedes-Benz data card by VIN

Frequently asked questions

What are the most common Mercedes-Benz GLB problems?

The best-documented Mercedes-Benz GLB issues are front axle integral carrier may corrode and fail (X247, 2020–2021), water may enter the front footwells and damage electronics (X247, 2020), driver door-lock micro-switch may corrode (rollaway risk) (X247, 2020–2026) and MBUX display may stay black, affecting the rearview camera (X247, 2020–2021). How much each matters depends on the chassis code and engine, so check the section for the exact car you are looking at.

Has the Mercedes-Benz GLB had any safety recalls?

Yes. Recalls covered on this page include front axle integral carrier may corrode and fail (NHTSA 21V-990), water may enter the front footwells and damage electronics (NHTSA 21V-403), driver door-lock micro-switch may corrode (rollaway risk) (NHTSA 26V-481) and MBUX display may stay black, affecting the rearview camera (NHTSA 21V-354). Recall repairs are free at a Mercedes-Benz dealer; check any specific car’s VIN with NHTSA to see whether its recall work was completed.

What should I check before buying a used Mercedes-Benz GLB?

Inspect the front subframe and carrier for corrosion. Feel under the front floor mats for moisture. Test the door-open warning with the engine running. Restart the vehicle several times and select Reverse each time. A pre-purchase inspection by a Mercedes-Benz specialist covers these and pulls the service history.

Is the Mercedes-Benz GLB reliable?

The documented Mercedes-Benz GLB issues are recall campaigns rather than recurring wear-out failures, and recall repairs are done free by Mercedes-Benz dealers. On a used car, the key step is confirming every open recall has been completed for that VIN.

Sources

Issue descriptions are CarWhere’s own summaries of the sources below. Chassis codes covered: X247 (2020–present (X247 GLB)). Repair costs are shown only where a source states them and vary by shop and region.

  1. NHTSA recall 21V-354: MBUX display / rearview camera software (343,191 units) — NHTSA
  2. NHTSA recall 21V-403: GLB footwell water intrusion (5,680 units) — NHTSA
  3. NHTSA recall 21V-990: Front axle integral carrier corrosion (38,312 units) — NHTSA
  4. NHTSA recall 26V-481: Driver door-lock micro-switch corrosion (rollaway) (310,667 units) — NHTSA

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Independent reference compiled by CarWhere — not affiliated with or endorsed by Mercedes-Benz Group AG or Mercedes-Benz USA. Mercedes-Benz, AMG, Maybach and the model names are trademarks of their owner.