ELECTRICAL SYSTEM:WIRING
2021 Mercedes-Benz GLS450
Recalls, owner-reported complaints, investigations and safety data
Data refreshed
Overview
Our database contains 30 NHTSA owner-reported complaints for the 2021 Mercedes-Benz GLS450, most frequently naming the electrical, driver assistance and engine categories. 12 safety recalls have been issued covering this model year; and 249 manufacturer communications are on file.
Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.
Complaint activity over time
When owners filed reports about this model year
View as table
| Month | Complaints filed | Cumulative |
|---|---|---|
| Jul 2021 | 1 | 1 |
| Dec 2021 | 1 | 2 |
| Mar 2022 | 1 | 3 |
| Apr 2022 | 1 | 4 |
| May 2022 | 1 | 5 |
| Jun 2022 | 1 | 6 |
| Aug 2022 | 1 | 7 |
| Sep 2022 | 1 | 8 |
| Oct 2022 | 3 | 11 |
| Nov 2022 | 1 | 12 |
| Jan 2023 | 5 | 17 |
| Sep 2023 | 1 | 18 |
| Oct 2023 | 1 | 19 |
| Dec 2023 | 1 | 20 |
| Apr 2024 | 1 | 21 |
| Jul 2024 | 1 | 22 |
| Aug 2024 | 1 | 23 |
| Sep 2024 | 3 | 26 |
| Nov 2024 | 1 | 27 |
| Jan 2025 | 1 | 28 |
| May 2025 | 1 | 29 |
| Nov 2025 | 1 | 30 |
What owners report
Complaints grouped by the component NHTSA recorded
- Electrical1446.7%
- Driver assistance413.3%
- Engine310.0%
- Interior & seats26.7%
- Seat belts13.3%
- Tires & wheels13.3%
- Body & structure13.3%
- Visibility13.3%
Percentages are of component mentions. A single complaint can name more than one component, so these do not sum to the total complaint count.
Safety recalls
12 campaigns cover this model year
Recalls apply to specific vehicles, not to every vehicle of a model year. Check your VIN with NHTSA or your manufacturer's dealer to confirm whether a recall affects your vehicle.
Check a VIN on NHTSA.govPOWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE
FUEL SYSTEM, GASOLINE:DELIVERY:FUEL PUMP
Recent owner complaints
Reports submitted to NHTSA, shown in the owner's own words
Both rear wheels on this vehicle have developed cracks which leads to tire pressure loss. Apparently, this is a common issue with Mercedes' heavier vehicles like the GLS and S series sedans. To be clear, I did not hit anything. I did not do any unusual driving. Both rear tires are fine. While you expect that certain components on a vehicle will have problems, it is also reasonable to expect that wheels will not crack prematuraly. Mercedes is aware of the problems. They were named in a class action lawsuit that was dismissed because cars were out of warranty. Warranty or no warranty, this is a major safety issue as a loss in tire pressure can be catastrophic.
- NHTSA ID
- 11701188
- Incident
- Oct 6, 2025
On [XXX], I was heading home from work traveling [XXX] on [XXX] through Atlanta's usual heavy traffic. I smelled smoke inside my car and saw fire flames coming from under my passenger seat. My initial reaction was to try to put the fire out with my hat without burning myself. Also, I had to try to navigate across multiple lanes of traffic without hitting anyone and avoiding anyone hitting me. Safely, i reached the side of the interstate and exited the vehicle. As I stood from afar watching my vehicle burn; the reality sat it that a few minutes earlier that could have been me trapped burning inside, injured or even death because something had failed in my vehicle. Later, when I finally arrived home, I started researching on the internet to see if anyone else had experienced problems with their MB 450 GLS catching fire. Surprisingly, I found that recalls had been issued in April 2022 and March 2024 for a possible fire risk from a 48volt loose ground wire issue under the passenger seat. At that time supposedly there were no reported injuries or crashes related to this issue until now. If I am the first to witness this issue, then so be it because I saw the fire burning from inside under my passenger seat before it FULLY torched my vehicle I reported this issue first to Progressive Insurance and Mercedes-Benz Corporate. Progressive has provided my transportation according to policy for my first 30 days. As I approached the end of my rental period, I spoke with MB Corporate to see if there was anything that they could do as far as providing me transportation. I was told that there was nothing that they could do because they were not a dealership with cars to loan. The joint vehicle fire investigation was schelduled for 29 April 2025. On 25 April 2025, Progressive informed me that MB Corporate had moved the fire investigation date to 29 May 2025. NOW, what am I suppose to do? It has been almost two months that I have been without a vehicle. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMAT
- NHTSA ID
- 11661377
- Incident
- Mar 27, 2025
System malfunctioned detail: 48v battery malfunction, 12v battery malfunction. Safety concern: I was driving on [XXX] , the battery malfunction warning suddenly pop up, and I couldn't accelerate my car beyond 30 MPH, my whole family were on the car during that time. it's life threatening issue needs to be addressed. Luckily we managed to pull over to a safe border way. It's first time I encountered this issue, but on [XXX] , seems like many people encountered it. Dealer is inspecting the issue currently. orange warning msg pop up first says "48v battery malfunction", few minutes later become red warning msg, while I pulled my car to the sideway, it became red "12v battery malfunction". INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
- NHTSA ID
- 11634240
- Incident
- Jan 4, 2025
Vehicle has just over 31k miles. ON multiple occasions, the vehicle randomly shuts off and displays a 48 volt battery error on the screen followed by a check engine light. This has happened in the middle of a busy intersection and at 75mph on the interstate. Each time it does this, I have taken it to a Mercedes dealer for repair/troubleshooting. THey perform the Mercedes required steps to repair the known issue and each time the issue persists. The car has been at a dealership for almost a combined 30 days now with no end in sight. I do not feel safe knowing that Mercedes cant seem to solve the problem and instead puts me back on the road knowing the car is not right and risks injury to my family as the issue has happened at low speed and high speed resulting in extremely dangerous situations for my family. I have 2 open PTSS cases with Mercedes USA (246121906 and 246113294). Researching this issue has revealed this is a known issue with their "mild hybrid" SUVS and many consumers have the same or similar experience to mine.
- NHTSA ID
- 11624928
- Incident
- Oct 15, 2024
I was driving only 30mph through my suburban neighborhood bringing my kids to school in the morning when a loud shotgun sound hit my car causing me to be distracted and distraught. My entire sunroof had exploded on me for no reason. Mercedes is currently undergoing a class action lawsuit for this. But since it is not completely yet, I’m being told I need to pay $3700 out of pocket for the default damages and servals days without a vehicle.
- NHTSA ID
- 11616529
- Incident
- Sep 25, 2024
Vehicle was purchased pre-owned. Mercedes Me is still associated with previous owner. Mercedes unable to remove association at dealership or on the phone. I can provide bill of sale and identification. Previous owner can remote start, track and control the vehicle I own. This presents a clear and obvious security and safety issue. I am not prepared to drive to *another* dealership and ask *again* to get this done. I own the car and the previous owner can do whatever they like with it. Unacceptable.
- NHTSA ID
- 11613731
- Incident
- Sep 9, 2024
Vehicle was purchased pre-owned. Mercedes Me is still associated with previous owner. Mercedes unable to remove association at dealership or on the phone. I can provide bill of sale and identification. Previous owner can remote start, track and control the vehicle I own. This presents a clear and obvious security and safety issue. I am not prepared to drive to *another* dealership and ask *again* to get this done. I own the car and the previous owner can do whatever they like with it. Unacceptable.
- NHTSA ID
- 11613729
- Incident
- Sep 9, 2024
1. Unknown, smoke started coming from under the passenger side seat, car is a complete loss. 2. Smoke damaged my lungs, there was a large amount of exploding glass, and it could have led to a structure fire. 3. Not applicable 4. In process, but it was recalled for this issue 5. No
- NHTSA ID
- 11610699
- Incident
- Aug 19, 2024
Manufacturer communications
A bulletin sent by a manufacturer to its dealers. Not a recall, and repairs are not necessarily free.
FUEL/PROPULSION SYSTEM
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’).
ELECTRICAL SYSTEM
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.
STEERING; STRUCTURE:BODY
Complaint Noise from front end attributable to steering gear. Cause During diagnostics of a front end noise, workshop is under the impression the noise is coming from the steering gear. Remedy Workshop diagnostics point to the steering gear as the root cause of the noise and the below LI's and items have been ruled out. • LI46.35-P-067339 - "Rattling or Humming Noise When Steering" • LI46.35-P-071461 - "Check Tie Rod Outer Joint of Steering Gear" • LI46.10-P-077391 - "Knocking Noise In The Area Of The Steering Gear or Steering Column Tube When Braking Or Moving Off; The Steering Wheel Can Also Be Felt To "Crack"" • If the noise is described as "clacking" or "knocking" and the thrust element in the steering rack has NOT been checked yet, please perform a check and subsequent adjustment, if necessary, as detailed in AR46.20-P-0601ME. If the above has been completed and the noise is still present, please continue with the below: • Video underneath the vehicle with clearly audible noise. • Video inside the vehicle with clearly audible noise. • Vehicle checked for history of collisions. • List of other checked components (suspension, drive line components, wheel bearings, etc...). • Check integrity of dust boots and dust boot clamps. Ensure no water has entered into the steering rack. • Along with the audible noise, does the feel/noise change through only a certain part of the steering arc sweep? • Provide the thrust element before and after readings. If the above is completed and no findings are noted, please open a TIPS case to the Body/Chassis/Entertainment inbox.
ELECTRICAL SYSTEM; STEERING
Complaint Hand detection system – malfunction / vehicles with code 266 Fault message in instrument cluster: "Active Emergency Stop Assist not available" "Active Lane Keeping Assist not available" "Active steering assist not available" Cause Possible causes: Hand detection mat, hand detection control unit, contacts, and electrical feed line. Remedy In the event of a customer complaint and fault code in IDC control unit: U186B29 in IDC223 or fault code U0429E0, U042941, U042929, U042902, U0429E1 in IDC213 or fault code in HOSWD control unit: B1E7614 Check: Please do not replace the HOSWD control unit. Please flash the new SW and perform the SCN coding for the HOSWD control unit (N179/1) (available from July 2026). The software can be flashed onto all HOSWD213 with HW number A0009011522 and all HOSWD223 with HW number A0009011422. Please also flash the SW for the IDC control unit (N62/4), if possible (only applies to HOSWD223). Erase fault memory Remedy: Turn on the ignition or start the engine without touching the steering wheel. If, after 10 seconds without touching the steering wheel, one of the three fault messages appears on the instrument cluster: Check the contacts and feed lines in the steering wheel by means of a visual inspection for damage, crimp connections, loose connections, etc. (example in picture 2 and 3). If there is visible damage -> replace the steering wheel electronics or the feed lines. If there is not any visible damage -> replace the steering wheel rim. If a yellow message does not appear on the instrument cluster within 10 seconds: Grasp the steering wheel fully with both hands, including the chrome molding at the 6 o'clock position (see picture 1). If the fault is triggered by grasping the steering wheel rim or pressing the clip at the 6 o'clock position, check the contacts and feed lines in the steering wheel by means of a visual inspection for damage, kinked connections, loose connections, etc. (example in picture 2 and 3). Check the ground connections (screw connections and cables to the steering wheel rim); if necessary, retighten the screws/bolts and check for corrosion (picture 4). If there is visible damage -> replace the steering wheel electronics or the feed lines. If there is not any visible damage: Replace the steering wheel rim. Please do not replace the HOSWD control unit. A TIPS case should be created if fault profile is unclear. In the event of a customer complaint and a further fault code in HOSWD: B1E7713: Check the ground connections (screw connections and cables to the steering wheel rim); if necessary, retighten the screws/bolts and check for corrosion (picture 4). B1F1F04: Check the control unit of the hand detection system; if necessary, replace this with the control unit from a donor vehicle (make sure that the hardware part numbers are identical).
POWER TRAIN
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).
ELECTRICAL SYSTEM
Complaint Traffic sign symbol for "Traffic Sign Assist" is blinking in instrument cluster without obvious cause usually with one of the following scenarios: • Flashing without a speed limit ("- -"). • Flashing when current vehicle speed is under speed limit. • Flashing between US speed limit symbol and European speed limit symbol. NOTE: • Verify that the concern falls under one of the attachment videos. If not, then it is outside of the scope of this LI. • This also does not cover "Traffic Sign Inoperative" messages on the instrument cluster. Cause There are two identified reasons for this concern: 1. Country code information stored incorrectly at a particular geographic latitude range. 2. Incorrect reference data when the vehicle is started and a GPS signal is not immediately available. Remedy Do not replace parts. Please open a TIPS case to the Body/Chassis/Entertainment inbox but read the below carefully: • The vehicle must be exhibiting the concern as shown in the attachment videos. • The vehicle DOES NOT need to be at the dealer, nor does it need to be brought into the dealership. • If the geographic location is known, it is very important that it is provided. • Provide any pictures or videos, if available. A new software for the head unit is scheduled for tentative release in Q3 2026.
Manufacturers file copies of the bulletins they send to dealers with NHTSA. These often describe diagnostic or repair procedures for a known condition. They are not recalls: repairs described in a bulletin are usually only free if the vehicle is still under warranty or the manufacturer has extended coverage.
Compare model years
Complaint and recall counts across every year of this model
Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers. Older model years have had longer for reports to accumulate.