2020 Mercedes-Benz GLS 450 problems and owner complaints
Explore the records behind recurring owner reports.
Key facts
35 owner complaints analyzed
20 distinct recall campaigns
6,550 mi median reported failure mileage
Scope: 2020 model year. Data snapshot: . 4 complaints include usable failure mileage.
Most common problems
Electrical System is the most frequently named component, appearing in 18 of 35 complaints (51.4%). A complaint can name multiple components.
| Topic | Matching reports | Share of complaints |
|---|---|---|
| Braking behavior | 12 | 34.3% |
| Electrical and battery issues | 12 | 34.3% |
| Engine operation | 4 | 11.4% |
| Transmission and shifting | 2 | 5.7% |
| Steering behavior | 2 | 5.7% |
Topic matches use published keyword rules. They describe mentions, including negations or comparisons, and do not confirm a diagnosis. Read the matching rules.
Component breakdown
Number of unique complaints naming each component. Top eight shown.
| Category | Count |
|---|---|
| Electrical System | 18 |
| Engine | 9 |
| Fuel/Propulsion System | 6 |
| Power Train | 4 |
| Unknown Or Other | 4 |
| Forward Collision Avoidance: Adaptive Cruise Control | 3 |
| Forward Collision Avoidance: Automatic Emergency Braking | 3 |
| Forward Collision Avoidance: Warnings | 3 |
Electrical System: 18; Engine: 9; Fuel/Propulsion System: 6; Power Train: 4; Unknown Or Other: 4; Forward Collision Avoidance: Adaptive Cruise Control: 3; Forward Collision Avoidance: Automatic Emergency Braking: 3; Forward Collision Avoidance: Warnings: 3
Reported problems by failure mileage
Complaint counts in mileage bands. These are not failure rates per vehicle or mile.
| Category | Count |
|---|---|
| Under 25,000 | 3 |
| 25,000 to 49,999 | 0 |
| 50,000 to 74,999 | 1 |
| 75,000 to 99,999 | 0 |
| 100,000 to 149,999 | 0 |
| 150,000 and above | 0 |
Under 25,000: 3; 25,000 to 49,999: 0; 50,000 to 74,999: 1; 75,000 to 99,999: 0; 100,000 to 149,999: 0; 150,000 and above: 0
Under 25,000 miles has the most reports with usable mileage (3). 31 complaints have missing, zero or invalid mileage.
Complaints over time
Year the complaint was filed, not the vehicle model year or incident year. The snapshot year is partial.
| Category | Count |
|---|---|
| 2020 | 2 |
| 2021 | 5 |
| 2022 | 4 |
| 2023 | 3 |
| 2024 | 8 |
| 2025 | 6 |
| 2026 | 7 |
2020: 2; 2021: 5; 2022: 4; 2023: 3; 2024: 8; 2025: 6; 2026: 7
Pattern summary
Electrical System leads the component reports. Braking behavior appears in 12 complaint narratives. Electrical and battery issues appears in 12 complaint narratives. Engine operation appears in 4 complaint narratives. Use these patterns to inspect individual reports and prepare questions for a mechanic.
Calculated from recorded counts. An AI narrative has not been published for this selection.
Complaint evidence
Examples provide context, not a representative sample or a verified diagnosis.
Owner report 11402929 · 2021-03-14 (March 14, 2021)
WE PURCHASED A NEW 2020 MERCEDES BENZ GLS 450 IN OCTOBER 2019 FROM THE OAKLAND DEALERSHIP AND SHIPPED THE CAR TO HAWAII. THE VEHICLE IS NOW 117 MONTHS OLD AND HAS ABOUT 4100 MILES. BECAUSE OUR VEHICLE IS LIGHTLY USED WE ARRANGED FOR MERCEDES BENZ TO SUPPLY AND INSTALLED A 'BATTERY MINDER' TO KEEP THE VEHICLES 48 VOLT SYSTEM CHARGED WHEN WE ARE AWAY FOR AN EXTENDED TIME. HOWEVER WE DID NOT HAVE THE BATTERY MINDER HOOKED UP AT THIS TIME BECAUSE WE ARE USING THE VEHICLE ON A WEEKLY BASIS. ON MARCH 7, 2021 WE EXPERIENCED A "48 VOLT BATTERY MALF…
Owner-reported narrative. 4,200 miles reported. Look up ODI 11402929 at NHTSA ↗
Owner report 11427911 · 2021-08-05 (August 5, 2021)
We were driving the vehicle at about 30 MPH on a road when suddenly the engine completely shut off. There was no more power steering and no warning that it turned off. We got the car slowed down and once we came to a stop the car put itself in Park. After that we could restart it and keep driving with the car acting very different. This then happened again later on in the day going about 20 MPH up to a stop light. It shut itself off and luckily we were able to come to a stop with the brakes without running into the intersection and no one hitti…
Owner-reported narrative. Look up ODI 11427911 at NHTSA ↗
Owner report 11343628 · 2020-08-06 (August 6, 2020)
WHILE DRIVING THE VEHICLE, A SERIES OF ELECTRICAL SYSTEM WARNINGS WERE DISPLAYED IN RAPID SUCCESSION. SHORTLY THEREAFTER, THE VEHICLE LOST POWER, THE ENGINE SHUT OFF, AND THE VEHICLE BEGAN TO GLIDE. THIS INCIDENT OCCURRED ON A RESIDENTIAL STREET WHILE THE VEHICLE WAS TRAVELLING AT 25-30 MPH. THE WARNINGS WERE SPECIFIC TO THE 48V ELECTRICAL SYSTEM. THE VEHICLE WAS OPERABLE AFTER THE INCIDENT AND IT WAS DRIVEN TO THE DEALERSHIP. THE REPAIR INVOICE AND THE WARNING PICTURES ARE ATTACHED. THE ISSUE WAS TRACED TO A GROUNDING ISSUE AS MOST OF THE CONN…
Owner-reported narrative. 8,900 miles reported. Look up ODI 11343628 at NHTSA ↗
Owner report 11439135 · 2021-11-02 (November 2, 2021)
The vehicle warnign system displayed "48v Malfunction." Vehicke lost all acceleration in the middle of the highway. The vehicle was just returned3 days ago after undergoing a state inspection at the MB dealership. In looking at the issue on line this appears to be a known problem to Mercedes. They are even facing a class action lawsuit for it in the same model year GLE, which is based on many of the same systems. SOmeone is going to get killed when their vehicle stalls in the middl eof the highway.
Owner-reported narrative. Look up ODI 11439135 at NHTSA ↗
Owner report 11653819 · 2025-04-10 (April 10, 2025)
On numerous occasions the transmission does not fully down shift to the next lower gear and then when I have to accelerate quickly it will drop down to the lower gear like it’s supposed to but won’t shift out to the next higher gear and when I let my foot off the accelerator the truck slows down quickly like applying the brakes which almost had me rear ended a few times and now the adaptive cruise control is malfunctioning
Owner-reported narrative. Look up ODI 11653819 at NHTSA ↗
Owner report 11486139 · 2022-09-23 (September 23, 2022)
This incident occurred around 5:50pm on Wednesday, September 21, 2022. I was driving on a merge connector between two freeways in San Francisco at about 60mph, when the vehicle threw a series of error codes and warnings on its displays, culminating with “shut down engine immediately”. The first error was a 48V battery system charging failure, and the second was a warning that coolant was too hot. The instrument panel and steering and brakes did not lose power, but the accelerator no longer worked, and the vehicle slowed down to about 35mph. …
Owner-reported narrative. Look up ODI 11486139 at NHTSA ↗