AMENDMENT TO ACTIVE CASE 11723015. CRITICAL AIRBAG & SAFETY DEFECTS. This files a safety defect amendment to open case 11723015. Diagnostic scans confirm central data bus network collapse on VIN [XXX] has migrated into safety-critical occupant restraint and visibility modules, violating 49 U.S.C. § 30118. I. AIRBAG & RESTRAINT HAZARDS Scans from [XXX], document active faults: DTC U042782: "Implausible data received from Electronic Ignition Lock." The SRS module receives corrupted data from the failed ignition gateway, creating risk of airbag non-deployment. DTC B007A13: Passenger seatbelt pre-tensioner open circuit; occupants are unprotected against crash displacement. DTC B11FA4B: Active "Overtemperature" faults in heating elements indicate localized thermal short-circuit risk. II. HARDWARE DECAY Physical teardown confirmed structural oxidation on the central gateway motherboard and corroded connector pins. Modular swaps failed; network lock code U016887 returned within 8 months. Raw dealer records are available for federal inspection. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
The worst 2020 Mercedes-Benz GLS 450 problems
Ranked by number of owner complaints. Mileage and cost come from what owners wrote.
Problems by type
Tap a problem to see which part fails, at what mileage and in which other years.
- Electrical18
- Engine9
- Driver assistance7
- Fuel system7
- Transmission4
- Airbags2
- Body2
- Brakes2
- Visibility2
- Acceleration1
- Seats1
- Steering1
- Suspension1
Specific symptoms reported on the 2020 Mercedes-Benz GLS 450
Recalls 22
Electrical system: wiring
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2023-2024 GLE 350, 2020-2024 GLE 450, 2020-2023 GLS 580, GLE 580, 2019-2023 GLS 450, 2021-2023 Maybach GLS 600, AMG GLS 63, 2021-2024 AMG GLE 53, AMG GLE 53 Coupe, and AMG GLE 63 S vehicles. A 48-Volt ground connection under the passenger seat may not be secured properly, resulting in the ground connection overheating.
- Risk
- An overheated ground connection can increase the risk of a fire.
- Remedy
- Dealers will inspect and tighten the 48-Volt ground connection as necessary, free of charge. Owner notification letters were mailed on May 3, 2024. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2024040002.
Recall number 24V207000 · Recall details
Power train: automatic transmission: control module: software
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020-2023 GLE 450 and GLS 450 vehicles. The transmission may not fully downshift in certain conditions, causing the engine to stall.
- Risk
- An engine stall increases the risk of a crash.
- Remedy
- Dealers will update the transmission control unit software, free of charge. Owner notification letters were mailed March 29, 2024. Owners may contact MBUSA customer service at 1‑800‑367‑6372.
Recall number 24V118000 · Recall details
Visibility: defroster/defogger/HVAC system
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020-2021 GLE350, GLE450, GLS450, GLS580, 2021 AMG GLE53, AMG GLE63, Maybach GLS600, AMG GLS63, and 2020 GLE580 vehicles. The air conditioner drain hoses may have been incorrectly installed, causing water to drain into the passenger compartment.
- Risk
- Water intrusion into the foot wells may cause corrosion and/or short circuits to electrical components, increasing the risk of fire. In addition, the emergency call (eCall) feature may be disabled and the doors may not unlock, increasing the risk of injury. Also, the engine may not start or may enter a limp-home mode, increasing the risk of a crash.
- Remedy
- Dealers will inspect and reinstall the air conditioner drain hoses, as necessary, free of charge. Owner notification letters were mailed April 28, 2023. Owners may contact MBUSA customer service at 1‑800‑367‑6372. This recall is an expansion of recall numbers 21V‑288 and 19V‑587. MBUSA's numbers for this recall are 2023030014 and 15.
Recall number 23V177000 · Recall details
Seats: mid/rear assembly
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 AMG GLS63, 2020-2022 GLS450 and GLS580 vehicles. Due to a manufacturing error, the locks on the third-row seatbacks may fail in the event of a crash.
- Risk
- A seat with a seatback lock failure may not properly restrain occupants, increasing the risk of injury during a crash.
- Remedy
- Dealers will inspect and replace the third-row seatback, as necessary, free of charge. Owner notification letters were mailed November 18, 2022. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2022100011.
Recall number 22V732000 · Recall details
Structure: body
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020-2022 GLE350, GLE450, GLS450, 2021-2022 AMG GLE53, 2020-2021 GLE580, GLS580, and 2021 GLE400e, AMG GLS63, AMG GLE63 S, and Maybach GLS600 vehicles. Due to a manufacturing error, the rear door window trim bars may detach.
- Risk
- Detached trim bars may cause a road hazard and increase the risk of a crash or injury.
- Remedy
- Dealers will inspect and secure the rear window trim bars, as necessary, free of charge. Owner notification letters were mailed November 1, 2022. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2022090010.
Recall number 22V680000 · Recall details
Air bags: frontal
- What is wrong
- Mercedes-Benz, LLC (MBUSA) is recalling certain 2020 Mercedes-Benz GLS 450 and GLS 580 vehicles. The front air bag wiring harness may be routed incorrectly, which can cause the air bag not to deploy properly. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 208, "Occupant Crash Protection."
- Risk
- An air bag that does not deploy properly can increase the risk of injury in the event of a crash.
- Remedy
- Dealers will correct the wiring harness routing, free of charge. Owners notification letters were mailed August 22, 2022. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2022070006.
Recall number 22V466000 · Recall details
Electrical system: software
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2022 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, AMG GT-Class, C-Class, E-Class, S-Class, SL-Class, GLC-Class, CLS-Class, GLB-Class, and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. An error in the communication module's SIM card software can cause a mobile network connection failure, disabling the emergency call (eCall) system.
- Risk
- A disabled eCall system would prevent a vehicle occupant from contacting the emergency services call center in an emergency, potentially delaying emergency responders and increasing the risk of injury.
- Remedy
- The communication module software will be updated through an Over-the-Air (OTA) update or by a dealer, free of charge. Owner notification letters were mailed July 8, 2022. Owner notification letters will be mailed in phases, on July 8, 2022, May 17, 2024, July 29, 2024, and September 27, 2024. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's numbers are for this recall is 2022060005 and 2023110006.
Recall number 22V365000 · Recall details
Electrical system: wiring: interior/under dash
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020-2022 GLE450, GLS450, 2021-2022 AMG GLE53, 2020-2021 GLE580, GLS580, 2021 AMG GLE63, Maybach GLS600 and AMG GLS63 vehicles. A ground cable bolt for the 48V ground connection under the front passenger seat may not be secured properly, which can cause the electrical cable to overheat.
- Risk
- An overheated electrical cable can increase the risk of a fire.
- Remedy
- Dealers will inspect and tighten the ground cable bolt, as necessary, free of charge. Owner notification letters were mailed July 8, 2022. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2022040017.
Recall number 22V231000 · Recall details
Back over prevention: display function
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2018-2021 CLA-Class, GLE/GLS-Class, A-Class, C-Class, E-Class, E-Class Coupe/Convertible, GLA/GLB-Class, GLC-Class, and CLS-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. The rearview camera may not display the rearview image due to a software error. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 111, "Rear Visibility."
- Risk
- An inoperable rearview camera display reduces the driver's rear view, increasing the risk of a crash.
- Remedy
- Dealers will update the rearview camera software, free of charge. Owner notification letters were mailed July 15, 2022. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2022060007.
Recall number 22V232000 · Recall details
Fuel system, gasoline: fuel injection system: fuel rail
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2019 AMG G63, C300, E300, G550, AMG GT63, AMG GT53, 2019-2020 A220, GLA250, GLC300, 2016 C300, 2020 AMG A35, AMG C43, AMG C63, CLA250, E350, E450, GLB250, GLE450, GLS450, GLS580, S560, and SL550 vehicles equipped with a gasoline engine. During the manufacturing process, particles may have been trapped between the fuel rail and injectors, which can cause a fuel leak.
- Risk
- A fuel leak in the presence of an ignition source, such as hot engine or exhaust components, can increase the risk of a fire.
- Remedy
- Dealers will replace the fuel rail and fuel injectors, free of charge. Owner notification letters were mailed April 22, 2022. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for the recall is 2022030003.
Recall number 21V961000 · Recall details
Seats
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020 GLS450, GLS580, GLE350, GLE450, AMG C63, and 2021 AMG GLE53 vehicles. The seats may have been assembled incorrectly.
- Risk
- Incorrectly assembled seats may not properly restrain an occupant during a crash, increasing the risk of injury.
- Remedy
- Dealers will inspect and repair the seats, as necessary, free of charge. Owner notification letters are expected to be mailed December 8, 2021. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2021110010.
Recall number 21V818000 · Recall details
Back over prevention: sensing system: camera
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2019-2021 CLA-Class, GLE/GLS-Class, A-Class, E-Class, E-Class Coupe and Convertible, GLA/GLB-Class, GLC-Class, CLS-Class, and AMG GT-Class 4-door Coupe vehicles. Please refer to MBUSA's recall report for specific vehicle model details. The MBUX multimedia system software may cause the display to remain black, or reboot after startup. This could result in the rearview camera image not displaying properly. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 111, "Rear Visibility."
- Risk
- A backup camera that displays a blank image reduces the driver's rear view, increasing the risk of a crash or injury.
- Remedy
- The multimedia system software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. Owner notification letters were mailed beginning June 28, 2021. Owners may contact MBUSA customer service at 1‑800‑367‑6373. MBUSA's number for this recall is 2021050012.
Recall number 21V354000 · Recall details
Equipment: appliance: air conditioner
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 AMG GLE 53, 2020 GLE350, GLE450, GLE580, GLS450, and GLS580 vehicles. The air conditioner drain hoses may have been incorrectly installed, causing water to drain into the passenger compartment.
- Risk
- Water intrusion into the driver and passenger side foot wells may cause corrosion and/or short circuits to electrical components, increasing the risk of fire. In addition, the emergency call (eCall) feature may be disabled and the doors may not unlock, increasing the risk of injury. Also, the engine may not start or may enter a limp-home mode, increasing the risk of a crash.
- Remedy
- Dealers will inspect and correct the air conditioner drain hoses, as necessary, free of charge. Owner notification letters were mailed June 4, 2021. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2021040024.
Recall number 21V288000 · Recall details
Electronic stability control (ESC): control module: software
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020-2021 GLE450, GLE350, and 2020 GLS450, GLE580, GLS580 vehicles. During certain evasive driving maneuvers, the Electronic Stability Program (ESP) software may apply torque to one of the front wheels, pulling the vehicle to one side. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 126, "Electronic Stability Control Systems."
- Risk
- If the vehicle unexpectedly pulls to one side during an evasive maneuver, it can increase the risk of a crash.
- Remedy
- MBUSA will notify owners, and dealers will update the ESP software, free of charge. The recall began March 31, 2021. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2021030004.
Recall number 21V071000 · Recall details
Structure: interior panels: dashboard
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020 GLS 450, GLE 350, GLE 450, and 2021 AMG GLE53 vehicles. The dashboard surface may not be properly secured to the base material.
- Risk
- In the event of a crash where the passenger air bag deploys, an unsecured dashboard could impair the inflation of the passenger air bag, increasing the risk of injury.
- Remedy
- MBUSA will notify owners, and dealers will replace the dashboard, free of charge. The recall began April 16, 2021. Owners may contact MBUSA customer serviced at 1‑800‑367‑6372. MBUSA's number for this recall is 2021030003.
Recall number 21V057000 · Recall details
Electrical system: software
- What is wrong
- Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2016 - 2021 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, GT-Class, C-Class, E-Class, S-Class, CLS-Class, SL-Class, B-Class, GLB-Class, GLC-Class, and G-Class vehicles. Please refer to the Part 573 report for specific vehicle model details. The software design of the communication module may fail to communicate the correct vehicle location for the emergency call system (eCall) in the event of a crash.
- Risk
- Failure of the eCall system may result in emergency responders being dispatched to the wrong location, increasing the risk of injury following a crash.
- Remedy
- MBUSA will notify owners, and the communication module software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. The recall began March 12, 2021. Owners may contact MBUSA customer service at 1‑877‑762‑8267. MBUSA's number for this recall is 2021020025.
Recall number 21V058000 · Recall details
Steering: electric power assist system
- What is wrong
- Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2020 GLE 350, GLE 450, GLE 580, GLS 450, GLS 580 vehicles equipped with an optional illuminated Mercedes-Benz star logo in the front grill. The star logo's electrical ground connection may not be installed properly, potentially affecting the function of other components that share the same ground connection, such as the power steering control unit, wiper motor, and/or the left headlight.
- Risk
- If the power steering, wiper motor, or left headlight malfunction there could be an increased risk of a crash.
- Remedy
- MBUSA will notify owners, and dealers will relocate the ground connection, free of charge. The recall began November 13, 2020. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2020100015/6.
Recall number 20V626000 · Recall details
Suspension: rear: shock absorber
- What is wrong
- Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2020 GLE450, GLS450, and GLS580 vehicles. The sealing of the piston assembly in the front struts and rear shock absorbers may leak and fail prematurely.
- Risk
- Premature wear of the front struts and rear shock absorbers can affect vehicle handling and control, increasing the risk of a crash.
- Remedy
- MBUSA will notify owners, and dealers will replace the front strut assemblies and rear shock absorbers, free of charge. The recall began October 20, 2020. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2020090001.
Recall number 20V329000 · Recall details
Structure: frame and members
- What is wrong
- Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2020 GLE350, GLE450 AND GLS450 vehicles. The seams on the rear crossmember may have been insufficiently welded. This may allow cracks to form when towing, possibly causing the rear crossmember to detach from the vehicle.
- Risk
- If the rear crossmember detaches from the vehicle, it can become a road hazard and increase the risk of a crash.
- Remedy
- MBUSA will notify owners, and dealers will replace the rear crossmember, free of charge. The recall began July 17, 2020. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2020060013.
Recall number 20V172000 · Recall details
Electrical system: instrument cluster/panel
- What is wrong
- Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2020 CLA250, CLA250 4MATIC and CLA35 AMG 4MATIC, 2020-2021 GLE350, GLE350 4MATIC, GLE450 4MATIC, GLS450 4MATIC and GLS580 4MATIC and 2021 GLE53 AMG Coupe, GLE63S AMG 4MATIC, GLS63 AMG 4MATIC and Maybach GLS600 4MATIC vehicles. The instrument cluster software may deactivate the illumination of certain interior switches (switch bar, overhead control unit, steering wheel) if the hazard lights are turned on and the ignition switch is in the 'off' position. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 101, "Control and Displays."
- Risk
- If the interior switches are not illuminated, they may be more difficult to find and operate, increasing the risk of a crash.
- Remedy
- MBUSA will notify owners, and dealers will update the instrument cluster software, free of charge. The recall began March 31, 2020. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2020030019.
Recall number 20V089000 · Recall details
Structure: body: door: hinge and attachments
- What is wrong
- Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2020 GLE350, GLE350 4MATIC, GLE450 4MATIC, GLS450 4MATIC, and GLS580 4MATIC vehicles. The rear door window trim may detach.
- Risk
- The detached trim can become a road hazard, increasing the risk of a crash.
- Remedy
- MBUSA will notify owners, and dealers will inspect and fasten the rear door window trim, as necessary, free of charge. The recall began November 8, 2019. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2019100011.
Recall number 19V709000 · Recall details
Equipment: appliance: air conditioner
- What is wrong
- Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2020 GLE350, GLE350 4MATIC, GLS450 4MATIC, and GLE450 4MATIC vehicles. The air conditioner drain hoses may have been incorrectly installed, causing water to drain from the air conditioner into the passenger compartment.
- Risk
- If a significant volume of water enters the driver and passenger side foot wells, it might cause corrosion and/or short circuits to the electrical components in the area, increasing the risk of fire. In addition, the emergency call (eCall) feature may be disabled; the vehicle may not be able to be unlocked and/or started; and the engine limp-home mode might be activated during driving. These features increase the risk of an injury or crash.
- Remedy
- MBUSA will notify owners, and dealers will inspect and correct the air conditioner drain hoses, as necessary, free of charge. The recall began September 6, 2019. Owners may contact MBUSA customer service at 1‑800‑367‑6372. MBUSA's number for this recall is 2019080005.
Recall number 19V587000 · Recall details
Technical service bulletins for the 2020 Mercedes-Benz GLS 450 271
Bulletins tell dealers how to fix known problems. A warranty extension means the manufacturer pays for that repair for longer.
- Dear Mercedes-Benz Owner: In our continuing efforts to ensure the proper performance of Mercedes-Benz...
- Fuel/propulsion system
- In our continuing efforts to ensure the proper performance of Mercedes-Benz products and to enhance the...
- Customer concern of Air Conditioning not cooling
- Sporadic warning message in instrument cluster "Engine oil pressure, stop switch off vehicle" (or similar)...
- Customer complaints relating to automatic transmission 725.0 (NAG3 Classic /9G‑TRONIC automatic...
- Slight creaking noises when steering
- Repeat workshop visit for vehicle vibration while braking from 60MPH. NOTE: Although the symptom is...
- Red coolant warning in instrument cluster
- Radio station cover art does not refresh when switching stations
2020 Mercedes-Benz GLS 450 fuel economy
Official EPA estimates in miles per gallon (MPGe for electric). Ranges cover trims that share the same engine.
| Engine | Drive | City | Highway | Combined |
|---|---|---|---|---|
| 3.0L 6‑cyl Hybrid | 4WD | 19 | 23 | 21 |
What 2020 Mercedes-Benz GLS 450 owners say
Most recent owner complaints, unedited.
The contact owns a 2020 Mercedes Benz GLS. The contact stated that while driving on the highway, the rear door window trim bars on the passenger side detached from the window. The vehicle was taken to the dealer where they diagnosed as a rear door window trim detachment however the vehicle was not repaired. The manufacturer was not notified of the issue. The approximate failure mileage 65,000.
Window trim on the passenger rear window fell off while driving- it put others at risk by flying off the vehicle on the interstate- Mercedes Benz of Omaha quoted replacement of the window trim parts- no warning messages on dash
The engine wiring harness insulation near the ignition coil connectors prematurely deteriorated due to prolonged exposure to engine heat in the turbocharger/exhaust area. Multiple wiring connectors exhibited brittle, cracked insulation with exposed conductors. The degraded wiring began shorting within the ignition system, causing engine misfires, ignition circuit faults, and eventual loss of engine operation. While being operated by a rental customer the vehicle developed severe misfires followed by electrical shorting, smoke, localized flames in the engine harness area, and eventual engine shutdown. The flames self-extinguished after the electrical shorting stopped, but portions of the harness insulation showed thermal damage and overheating. The customer became stranded due to the vehicle becoming inoperable. Diagnostic faults included ignition coil circuit open faults and ignition primary circuit faults. The vehicle ultimately became inoperable due to the electrical failure. Inspection revealed multiple adjacent ignition harness connectors showing progressive heat-related insulation degradation in the same high-temperature area, indicating a broader harness material failure rather than isolated damage. This failure occurred on a 5-year-old vehicle. Engine wiring harness insulation should not prematurely degrade and short under normal operating conditions.
On a sunny afternoon without zero clouds in the sky, 75 degrees I was driving at 35 mph on a two-lane road with no cars in front of me, behind me, or coming in the other direction, the brakes were urgently and automatically applied and the seat belts dramatically tightened. The system showed a large red X on the screen. It was obvious the automated safety system mistakenly thought we were about to crash into something but there wasn't anything but smooth asphalt.
The vehicle (2020 GLS 450) suffers from terminal infrastructure "Electronic Rot," resulting in a consistent Breach of FMVSS 111 (Rearview Visibility) and dangerous Automatic Emergency Braking hallucinations. On 03/08/2026, a routine car wash triggered multiple system failures, including "Camera View Restricted" and "Adaptive Highbeam Assist Currently Unavailable," proving the electrical architecture is compromised by minor moisture. This is a multi-dealer failure: the vehicle was sold as "Certified Pre-Owned" by Mercedes-Benz of Fredericksburg with undisclosed active "Special Procurement" status; a 200-day attempted EIS remediation at i.g. Burton failed to resolve the hazards; and the regular service center, Mercedes-Benz of Annapolis, has failed to remediate the ongoing "Electronic Rot." All parties are currently withholding machine-level XENTRY diagnostic sequences required to verify the vehicle's safety status.
The vehicle is experiencing deterioration of the main engine wiring harness insulation, resulting in exposed wires contacting each other. This condition has caused intermittent check engine lights and electrical fault codes. The dealership has confirmed that the wiring insulation has degraded, allowing wires to contact each other. The issue appears related to material durability of the harness rather than external damage. The concern is that continued deterioration could result in: •Sudden engine misfire •Loss of power while driving •Engine stalling •Potential electrical short circuit An unexpected loss of engine power at highway speeds could increase the risk of a crash. The dealership indicated that similar harness insulation concerns have been observed on other M256-equipped vehicles. This appears to be a potential safety-related defect involving engine wiring insulation durability.
The sunroof spontaneously shattered while driving down the interstate. No other cars involved and no rocks or debris caused it. It was inspected and repaired at a Mercedes dealer, however, Mercedes refused to cover the repair under the pre-owned certified warranty. We had to file an insurance claim. In doing research, it appears this is a common and ongoing problem with various models of Mercedes.
The vehicle, 2020 Mercedes-Benz GLS450, was being backed out of the garage when an electrical failure occurred causing the vehicle to malfunction. This was a major safety issue that caused the entire vehicle electrical control systems to fail as the vehicle would not turn-off. The vehicle eventually turned-off and was not operational. It was towed to a local dealer where we were they discovered that a heating/cooling system hose caused moisture to enter the cab of the vehicle. The end result was major electrical damage to the vehicle control system of the vehicle. This vehicle is my wife's primary means of travel along with our 4 young children. Had this major malfunction occurred while on a highway going at high speeds a parish the thought of what could have happened to the safety of my wife and children. Per attached dealership bill, the dealership was not able to obtain coverage for this $4,255.15 repair bill. In addition, I did find other Mercedes-Benz GLS450 models who were recalled for this very safety issue where moisture in the cab resulted in major electrical control systems of the vehicle.
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
Compare the 2020 Mercedes-Benz GLS 450
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Questions about the 2020 Mercedes-Benz GLS 450
Is the 2020 Mercedes-Benz GLS 450 reliable?
Owners have filed 36 complaints about the 2020 Mercedes-Benz GLS 450, 1.2 times a typical GLS 450 model year.
What is the 2020 Mercedes-Benz GLS 450 year score?
The 2020 Mercedes-Benz GLS 450 scores 63 out of 100 (average). The score compares it with the other model years of the Mercedes-Benz GLS 450: 75 is a typical year, 50 means twice the usual complaints, and serious complaints and recalls lower it.
What is the most common problem with the 2020 Mercedes-Benz GLS 450?
Electrical system, with 18 complaints. Next is engine (9).
How many recalls does the 2020 Mercedes-Benz GLS 450 have?
22 recalls, covering electrical system, power train and visibility.
Was there a recall on the 2020 Mercedes-Benz GLS 450 electrical?
Yes, 5 recalls: 24V207000, 22V365000, 22V231000. Check your VIN to see if your car still needs the free repair.
What year does the Mercedes-Benz GLS 450 have the most electrical problems?
The Mercedes-Benz GLS 450 model years with the most electrical complaints are 2020 (18 complaints) and 2021 (14 complaints).
What gas mileage does the 2020 Mercedes-Benz GLS 450 get?
Official estimates for the 2020 Mercedes-Benz GLS 450 range from 21 mpg combined. The most efficient version (3.0L 6-cyl hybrid, 4WD) gets 19 city and 23 highway.
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