2023 Mercedes-Benz GLB 250

Safety Risk - Twice I was almost hit because my car didn't take off. O'REILLY Veri Scan Results - Free Emissions Status: Red Primary DTC: Mixture Formation (Cylinder 4) is irregular P219F: Fuel injectors measure and atomize fuel mixed with incoming air and sent to combustion chambers. Cylinder 4 PSI at 40 Mercedes Benz of San Juan $300 diagnostic Cylinder head needs to be replaced. Safety Risk - Twice I was almost hit because my car didn't take off. Problem has been confirmed by dealer. Not inspected by manufacturer, etc. Prior to failure there were no signs. Check Engine light came on and that is when it got checked at 55, 715 miles, soon after warranty ended.

NHTSA ID

11739111

Incident

Mar 31, 2026

My 2023 Mercedes-Benz GLB 250 is experiencing engine misfires and fault codes consistent with a known cylinder head defect that is the subject of a recall affecting 2022 and earlier models. A certified mechanic has confirmed the issue aligns with the recall defect. Despite identical symptoms and engine configuration, my VIN is excluded. The condition results in loss of power and creates a potential safety hazard while driving. The following codes are referenced in the Mercedes recall and by recorded by the auto repair shop that provided an estimate for the repair: P1CEF85 - Injector injection quantity adjustment for cylinder balancing has almost reached the upper limit value at atleast one cylinder. P1CE577 - Injector injection quantity adjustment for uniform mixture formation has detected an excessively lean mixture at atleast one cylinder.

NHTSA ID

11733918

Incident

Mar 5, 2026

Reporting because I see reports on other searches of this happening on other Mercedes Benz various years and models, the front stationary roof panel has shattered, cracked. I was lucky, my vehicle is only cracked (leaving my windshield components open to the weather , ie rain in Washington). Others report shattering while driving and having injuries from blowing glass. This appears to be an ongoing problem with Mercedes, they want over $2000 to fix a common problem with their vehicles.

NHTSA ID

11733638

Incident

Apr 24, 2026

On December 19, 2025, the vehicle showed lights that a sparkplug had misfired. The dealer notified me that in less than two full years of having the 2023 vehicle, it required a complete engine rebuild. This is the third major engine problem I have had with the vehicle with more than $20K in fees. The services performed in December 2025 repairs included Cylinder Head Assembly to Replace Engine Cylinder Head Assemble due to multiple cylinder head fault codes, including misfire, injector injection, and mixture formation code. Cylinder 2 is leaking out of the exhaust valve. Camshaft replacement and rollers due to deep scoring on both intake and exhaust cams, not by cylinder two. Exhaust valve leaking from the head while the camshafts are scoring, leading to misfiring as well.

NHTSA ID

11720803

Incident

Dec 19, 2025

Cylinder repair dealership said it's a known issue but Mercedes Benz said they will not cover the repair.

NHTSA ID

11698759

Incident

Nov 10, 2025

I was driving on Highway on May 19th and the Panoramic Sunroof suddenly shattered

NHTSA ID

11686651

Incident

May 19, 2025

Graco Turn2Me car seat is loosening over time when installed with the vehicle seatbelt and the SnugLock Lock-Off. The vehicle seat belt was also switched to a locked mode after proper installation and did not make a difference over time. The car seat continues to loosen over time to the point where it is moving more than an inch side to side at the belt path. This can cause injury to a child during a crash. Car seat has been installed with the assistance of certified Child Passenger Safety Technicians and Instructors on multiple occasions.

NHTSA ID

11672721

Incident

May 10, 2025

The windshield washer stopped working It doesn’t clean because no water comes out to do the job

NHTSA ID

11667787

Incident

Jun 17, 2025

This NCU replaces the prior NCU issued on May 15, 2025, and contains additional MY 2023 and MY 2024 vehicles which are highlighted below. In our continuing efforts to ensure the proper performance of Mercedes-Benz products and to enhance the satisfaction of our customers, Mercedes-Benz USA, LLC (“MBUSA”) is extending the warranty coverage on the Diagnostic Module for Tank Leakage detection (DMTL) in certain Model Year (“MY”) vehicles listed below from the original New Vehicle Limited Warranty of 4 years/50,000 miles to 10 years/120,000 miles (vehicles certified as LEV II) and 15 years/150,000 miles (vehicles certified as LEV III), whichever occurs first, for the following condition: •Under certain circumstances, the DMTL may trigger erroneous Diagnostic Trouble Code (DTC) entries that may result in the illumination of the Check Engine Malfunction Indicator Lamp (‘MIL’).

Complaint CEL light on with no drivability concerns. Cause Signal timing error. Remedy 167, 465: SW has been released. Update the FSAM to the latest SW version. 290, 118, 243, 247: Software is still in development. This fault code does not cause a drivability concern and will clear itself within 2-3 key cycles. The vehicle can be released back to the customer.

Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end). The noise is heard once in each instance when changing direction of travel. Note: Sound file in attachment Cause If the complaint is eliminated by experimentally loosening the outboard collar nut (by 1 turn), the problem is due to cracking of the microweld between the wheel bearing inner race and the joint housing of the side shaft. Note: The collar nut must always be replaced after being loosened. See also LI33.20-P-078406 Remedy Coat contact surface of side shaft with wheel bearing with Molykote paint. To do this, proceed as follows: 1. Remove side shafts 2. Clean contact surface A (see image file in attachment "Outer joint housing before") before coating with Molykote, using "spirit" (free of dust and grease) 3. Coat contact surface A (see image file in attachment "Outer joint housing after") with Molykote and leave to dry for "one hour" in removed condition 4. Reinstall side shafts Note: Before using the antifriction coating (Molykote), stir it or shake it thoroughly for (at least 1 minute).

Complaint Radio station cover art does not refresh when switching stations. The UI continues to show the old station’s artwork instead of updating to the new one. Cause When a new station change request is triggered, a temporary glitch is causing the Head Unit application to fail to overwrite the previous request. This glitch is causing the cover art mismatch in the Radio application. Remedy Please do not replace any parts. The E505.9 software is released and available in XENTRY Q3 2026.

Complaint CEL light on with no drivability concerns. Cause Signal timing error. Remedy 167: SW has been released. Update the FSAM to the latest SW version. 465, 290, 118, 243, 247: Software is still in development. This fault code does not cause a drivability concern and will clear itself within 2-3 key cycles. The vehicle can be released back to the customer.

Dear Mercedes-Benz USA Dealers, The part numbers listed in the chart below should no longer be installed, and any existing stock must be returned to your facing PDC. The deadline for all dealer returns is no later than Thursday, July 9, 2026. After July 9th, returns of these parts will no longer be accepted. These parts should be returned via ZSR Special Return, using item category SCM Authorized Part Return. Please include a copy of this NCU as your authorization to return these parts. This procedure will not affect your return allowance. All returned parts will be replaced in accordance with the chart provided below.