NHTSA (USA)Critical
At a glance
This page covers 20 recalls and 34 owner complaints for the 2020 Mercedes-Benz Gls 450.
Electrical complaints dominate the 2020 GLS 450 owner reports, with several describing wiring harness insulation that deteriorated prematurely near the ignition coil connectors in the turbocharger and exhaust area, owners report brittle, cracked insulation and exposed conductors. A separate pattern involves the rear door window trim detaching while driving at highway speeds, with multiple owners describing the trim strip separating from the passenger-side rear window without warning. Forward collision avoidance draws the next-highest complaint volume, where owners report the automatic emergency braking activating abruptly in clear conditions with no obstacle present, the brakes apply hard and the seatbelts tighten, accompanied by a warning on the display. Several of these AEB activation complaints also mention the backup camera losing function intermittently.
34
Total Complaints
2
Crash-Related
1
Fire-Related
1
With Injuries
By System
The 2020 Mercedes-Benz GLS 450 has 20 recalls, the most serious involving fire risks from an improperly secured 48-volt electrical ground connection under the passenger seat, a fuel injector leak near hot engine components, and incorrectly installed air conditioner drain hoses that let water pool in the footwells and short-circuit electrical components.
A transmission software issue can prevent a proper downshift and stall the engine without warning. The rear crossmember may have insufficient welds that allow it to crack during towing and drop from the vehicle entirely. On the suspension side, front struts and rear shock absorbers can lose their seals prematurely and affect handling. Vehicles with the optional illuminated front grille star logo have a separate wiring concern where power steering, the wiper motor, or the left headlight can malfunction.
Several occupant safety recalls affect this vehicle: incorrectly assembled front seats may not restrain occupants in a crash, the third-row seatback locks can fail in a crash, the front airbag wiring may be routed in a way that prevents proper deployment, and the dashboard surface can separate and interfere with the passenger airbag. The electronic stability software can pull the vehicle to one side during evasive maneuvers. On the visibility side, the backup camera display can go black or fail to load, and rear door window trim bars can detach and become road debris. The automatic emergency call system also has two separate software issues that can prevent it from reaching emergency services or transmit an incorrect location after a crash.
At a glance
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Complaints are owner-reported and reflect individual experiences, not confirmed defects. They are distinct from recalls. Data sourced from the national vehicle safety complaint database. See trending complaints →
What can fail
The 48-Volt ground connection under the passenger seat may not be properly secured, which can cause it to overheat.
What the fix does
Dealers will inspect and tighten the 48-Volt ground connection as needed at no cost to you.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The transmission may fail to downshift completely in certain conditions, which can cause the engine to stall.
What the fix does
Dealers will update the transmission control unit software at no cost to you.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
Air conditioner drain hoses may be incorrectly installed, allowing water to drain into the passenger compartment instead of outside the vehicle.
What the fix does
Dealers will inspect the air conditioner drain hoses and reinstall them correctly at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The locks securing the third-row seatbacks may fail during a crash due to a manufacturing error, potentially allowing the seatbacks to move unexpectedly.
What the fix does
Dealers will inspect and replace the third-row seatback as needed at no cost to you.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The trim bars around the rear door windows may come loose and detach due to a manufacturing error.
What the fix does
Dealers will inspect the rear window trim bars and secure them as needed at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The front air bag wiring harness may be routed incorrectly, preventing the air bag from deploying properly in a crash.
What the fix does
Dealers will correct the wiring harness routing at no cost to you.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
A software error in the communication module's SIM card can prevent mobile network connection, which disables the emergency call (eCall) system.
What the fix does
The communication module software will be updated at no cost through an over-the-air update or by a dealer.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The ground cable bolt for the 48V electrical connection under the front passenger seat may not be properly tightened, which can cause the cable to overheat.
What the fix does
Dealers will inspect and tighten the ground cable bolt as needed at no charge.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
A software error prevents the rearview camera from displaying the backup image on the screen.
What the fix does
Dealers will update the rearview camera software at no cost to restore the backup image display.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
Manufacturing debris may be trapped between the fuel rail and injectors, potentially causing fuel to leak.
What the fix does
Dealers will replace the fuel rail and fuel injectors at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The seats may have been assembled incorrectly during manufacturing, potentially affecting their function or safety.
What the fix does
Dealers will inspect your seats and repair them if needed at no cost to you.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The MBUX multimedia system software may cause the display to go black or restart after startup, preventing the rearview camera image from displaying properly.
What the fix does
A dealer will update the multimedia system software, or you can receive the update over-the-air, at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The air conditioner drain hoses may have been installed incorrectly, allowing water to drain into the passenger compartment instead of outside the vehicle.
What the fix does
Dealers will inspect the air conditioner drain hoses and correct the installation as needed at no charge.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
During sharp evasive maneuvers, the Electronic Stability Program software may apply torque unevenly to a front wheel, causing the vehicle to pull to one side.
What the fix does
Dealers will update the Electronic Stability Program software at no charge.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The communication module software may fail to send your vehicle's correct location to emergency services when the eCall system activates during a crash.
What the fix does
A dealer will update the communication module software, or the update will be sent over-the-air, at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The dashboard surface may not be properly secured to its base material, which could cause it to shift or separate.
What the fix does
Dealers will replace the entire dashboard at no cost to you.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The illuminated star logo in the front grille may have an improperly installed electrical ground connection, which could affect other components sharing that ground, including power steering control, wipers, and the left headlight.
What the fix does
Dealers will relocate the ground connection to restore proper electrical function.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The piston seals in the front struts and rear shock absorbers may leak, causing these suspension components to fail prematurely.
What the fix does
Dealers will replace the front strut assemblies and rear shock absorbers at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The welds on the rear crossmember may be weak, allowing cracks to develop during towing that could cause the rear crossmember to detach from the vehicle.
What the fix does
Dealers will replace the rear crossmember at no cost to you.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The air conditioner drain hoses may be incorrectly installed, allowing water to drain into the passenger compartment instead of outside the vehicle.
What the fix does
Dealers will inspect and correct the air conditioner drain hoses as needed at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.