2021 Mercedes-Benz G 550

Shortly after purchasing a new Mercedes Benz 2021 G550 on [XXX], the SUV started having electrical problems. During early 2022 the vehicle shut off while at a red light and would not restart until a few minutes later. No warning light or error message was seen and when taken to the dealership they could not find anything wrong. Several months later the vehicle stopped/stalled almost causing an accident on the highway. This time the dealership did find something wrong and repaired or replaced it. Not sure exactly what it was but they mentioned something electrical Several months after this error messages began to appear on the dashboard and the car would not start. A tow truck had to take it back to the dealership. The vehicle has now been at the dealership for 4 months since February 8, 2024. They tell us they are awaiting parts or some type of harness from Germany . We are requesting more detailed repair reports from the dealership. The car only has 12,000 miles driven. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11592609

Incident

Mar 10, 2022

The brakes locked up in the vehicle and computer system nearly causing deadly accident.

NHTSA ID

11566025

Incident

Jan 17, 2024

Authorization failed Limited access is the reason there recalled I can't pair ⁶

NHTSA ID

11540970

Incident

Aug 27, 2021

Driving 2021 Mercedes-Benz G-550 for approximately 8min. Preceding East on a 3 lane South Florida Highway no more than 40 mph. Gas tank 75% full with V-Power From Shell. (filled-3 days prior). Proceeded from the middle lane to the right lane in-order to make a sharp right handed turn onto up coming Shopping Center, that was two lights away. I had turned on my 21 MB G550 air conditioner to auto (off prior). While I was attempting to switch on my turn signal the car suddenly turns-off completely in mid-drive. All warning lights illuminated, steering this 6,000 lbs Mercedes-Benz Beast of a SUV became extremely difficult, as I was already in the sharp right handed turn! I immediately switched on my Mercedes-Benz hazards. I couldn’t apply my breaks immediately, because other vehicles were less then a car length behind my G550 in this single right handed sharp turn with no exterior lighting. I had to wait until my G-Wagon came to a complete stop on it’s own! It lost momentum pretty fast. If I would have panicked & had hit the breaks, I would have gotten into a very serious accident! Luckily, there was no one in front of my G 550 path! I then restarted my Mercedes-Benz-G, placed my 2021 G550 into drive! I proceeded to accelerate but my benz wasn’t moving! Less than 15 secs from the restart my Mercedes G550 jerked, then proceeded to get momentum again. G550 engine yellow light remained on until I got home! When I had restarted my Mercedes-Benz G-Wagon for the MBUSA tow truck, no engine light Illuminated! Then Decided to get towed in the am instead. Was extremely shaken-up, even hours later. An hour earlier that evening, My Mercedes G Wagon was parked for about 8 hours. When I started my Mercedes-Benz G 550, it had died before I could close the door! A month prior, 110 miles less, my Mercedes G550 died in mid-Drive twice in one day while attempting to stop for a red light (Engine auto on/off was enabled) Then died again while I was attempting to park.

NHTSA ID

11485579

Incident

Sep 20, 2022

While pulling away from a red light, the vehicle jolted a small amount, then it shut down, only providing power to the dashboard, which produced an array of safety warnings. Power steering and throttle were completely dead leaving me powerless in traffic. I pulled to the shoulder of the road, placed the vehicle in park (as it seems that the failure put the car into neutral). I was able to restart the vehicle and continue driving home with no warning lights or issues. (Several other owners are having this same issue-I found them by googling the problem). My vehicle has under 5k miles on it and is always stored indoors in a climate controlled environment.

NHTSA ID

11421207

Incident

Jun 16, 2021

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’).

Mercedes-Benz AG (“MBAG”), the manufacturer of Mercedes-Benz, has determined that on certain MY 2019-2021 C-Class, G-Class, GLC, GT, S-Class (205, 463, 253, 190 & 222 platforms) vehicles, the engine control unit software does not correspond to current production specifications. It is therefore possible that on-board diagnostics and/or exhaust gas emissions requirements may not be fulfilled.

Complaint Check Engine Light ON with DTC P012800 "The Coolant Temperature is Below the Specified Temperature" active and/or stored in the ME (N3/10). There are no drivability concerns related to this complaint. Cause Root cause varies Remedy Prior to performing any repairs for this complaint: With a cold engine, pressurize the high temp coolant circuit and while it's under pressure, release the cap on the low temp coolant circuit and check if the pressure drops right away or not. If the pressure drops, the lower coolant hoses are swapped. Correct this, fill, bleed and test drive the vehicle. If the complaint returns, then continue with the steps below. IMPORTANT: Use VMI to check for the following emission extended warranty –> Engine Thermostat (incl. software update) MY19-23, Various Models and Platforms (167, 190, 205, 213, 217, 222, 223, 232, 253, 290, 463) If the vehicle is covered under the above emission extended warranty, please perform steps outlined in the accompanying NCU prior to those outlined in this document. If vehicle is not covered under the above emission extended warranty or the complaint continues to occur, then proceed as follows: Check for available software updates to the ME (N3/10). If updated software is available, perform the update, clear the DTC and the perform each of the "WARM START" and "COLD START" test drives listed below twice. If the code does not re-appear then release the vehicle. If there is no new software available OR the DTC returns after the test drives then perform the following steps: • Drain the coolant through a fine mesh sieve and check for signs of debris. Additionally, inspect the coolant reservoir for debris. If any debris is found take pictures of the reservoir and the mesh filter and "flush" the system at least 2-3 times to clear as much of the debris as possible • Replace the thermostat and bleed the system as outlined in AR20.00-P-1142-04A, evacuate the system for 20-30 minutes instead of the 5 minutes specified in step 22 • NOTE: Please use all the tools specified in the AR document. The DTC will continue to populate if the circuit is not properly bled • NOTE: There are two valid thermostats to choose from in the parts section of this LI. Please verify which PN is applicable for the vehicle being worked on via XENTRY Parts Information • After bleeding the system clear the DTC and perform each of the "WARM START" and "COLD START" test drives listed below twice. If the DTC does not reappear after the tests, release the vehicle If the ME (N3/10) software is up to date, the thermostat has already been replaced, and the complaint persists open a TIPS case and attach the following documents: • Initial quick test • ME (N3/10) control unit log • The results of an R48 test from a “yes” response and from a “no” response • Pictures of the coolant reservoir and mesh sieve (mentioned above) WARM START · Begin with the engine coolant temperature at approximately 50 degrees C · Activate the AC system, if defrost is not in use open the windows · Drive the car normally until a coolant temperature of 75 degrees C is achieved · Depress the accelerator pedal 50% for ~5 seconds (partial acceleration) · Let off the accelerator pedal and let the car coast for ~10 seconds · Continue to drive the car normally COLD START · Drive for ~7 miles (normal driving) · Shut off the engine in a parking lot (or similar), wait 30 seconds, then restart and continue driving · Depress the accelerator pedal 50% for ~5 seconds (partial acceleration) · Let off the accelerator pedal and let the car coast for ~10 seconds · Continue to drive the car normally

Dear Mercedes-Benz USA Dealers, The part numbers listed in the chart below should no longer be installed, and any existing stock must be returned to your facing PDC. The deadline for all dealer returns is no later than Thursday, August 6th, 2026. After August 6th, returns of these parts will no longer be accepted. These parts should be returned via ZSR Special Return, using item category SCM Authorized Part Return. Please include a copy of this NCU as your authorization to return these parts. This procedure will not affect your return allowance. All returned parts will be replaced in accordance with the chart provided below.

Complaint Consistently reproducible erroneous parktronic warnings from front with every key cycle. Cause The parking sensors are detecting the front brush guard. Remedy Complaint must be consistently reproducible and can occur multiple times a key cycle without obvious cause. NOTE: The parking system serves solely as an aid. Please review both the system function and system limitations as shown in the Operator's Manual. Certain environmental factors can affect system functionality such as hot exhaust gases or extreme heat, sensor interference, or other outside influences or aftermarket modifications. If after verifying the complaint is consistently reproducible: 1. Determine if the complaint is reproducible only in high ambient temperatures. If complaint does not occur in cooler ambient temperatures, it is due to system limitations. You may proceed with the below work but the vehicle may be released afterwards as it is due to system limitations. 2. Remove the brush guard and verify the park distance sensors function as expected. 3. Reinstall brush guard and adjust so that it is as far away from the park sensors as possible. Typically only small adjustments are possible. 4. Check function. If the concern is still consistently reproducible, please apply clear matte film to the locations as shown below at a minimum, although the clear matte film may be applied to the whole brush guard.

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).