NHTSA (USA)Critical
At a glance
What can fail
The 48-Volt ground connection under the passenger seat may not be properly secured, which can cause it to overheat.
The 2021 Mercedes-Benz GLS450 has 12 recalls, the most serious being fire and stall risks: an unsecured 48-volt ground connection under the passenger seat can overheat and ignite, and the fuel pump or transmission can cut power while driving.
The fire risks extend further: incorrectly installed air conditioner drain hoses can let water pool in the footwells, where it can corrode wiring or cause electrical shorts. On the structural side, the rear window may not be adequately bonded to the tailgate and can detach while driving, and rear door window trim bars can also come loose, both creating road hazards. Third-row seatback locks may fail in a crash, leaving rear occupants without proper restraint.
Several recalls affect visibility and driver information. The backup camera display can go black or restart on startup, reducing rear visibility when reversing. Interior switches may lose their illumination, making them harder to locate while driving. Two separate recalls cover the emergency call system, which can either fail to connect or send responders to the wrong location after a crash. There is also a software issue where the transmission may not downshift properly, causing the engine to stall.
At a glance
What can fail
The 48-Volt ground connection under the passenger seat may not be properly secured, which can cause it to overheat.
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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
The fuel pump may shut down unexpectedly, causing a loss of engine power while driving.
What the fix does
Dealers will replace the fuel pump 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
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
The rear window may not be properly bonded to the tailgate, which could cause the rear glass to detach.
What the fix does
Dealers will replace the rear window 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 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 instrument cluster software may turn off the lights on certain interior switches (switch bar, overhead controls, steering wheel) when hazard lights are on and the ignition is off.
What the fix does
Dealers will update the instrument cluster software at no cost to restore proper switch illumination.
Summarized — see the official notice for exact wording, dates, and contacts.