2020 Mercedes-Benz AMG GLC63

The contact owns a 2020 Mercedes-Benz GLC63. The contact stated that while his wife was driving at highway speeds, the vehicle inadvertently decelerated while the accelerator pedal was being depressed. The check engine warning light illuminated, and a message displayed on the instrument panel stated that the “Transmission Needs to Cool, Stop and Pull Over Immediately”. The contact stated that the vehicle had locked in first gear and decelerated to approximately 55 MPH. Additionally, the contact stated that his wife was able to navigate the vehicle back to the residence. The contact stated that the following day the contact was able to restart the vehicle. The vehicle was taken to the dealer where it remained awaiting a diagnostic test. The vehicle had not yet been repaired. The manufacturer was notified of the failure and the contact was provided a case number. The failure mileage was approximately 24,000.

NHTSA ID

11549774

Incident

Oct 10, 2023

Mileage

24,000 mi

WHEN USING ENGINE START/STOP FUNCTION, OVER THE COURSE OF 3 DAYS AFTER PICKING UP THE CAR, WHEN AT A LIGHT, THE CAR DID NOT START BACK UP.

NHTSA ID

11373040

Incident

Nov 2, 2020

Mileage

8,900 mi

Complaint Repeat workshop visit for vehicle vibration while braking from 60MPH. NOTE: Although the symptom is similar to a tire or wheel vibration, it is usually readily noticeable that it is distinctly different if it happens at all times or only while braking. Cause Although the cause of the vibration is most likely due to excessive lateral runout on the rotor or hub/wheel bearing, the system as a whole needs to be checked for other possible contributors. 1. Prior collision damage. 2. Excessive vehicle sitting times without rotating components. 3. Wheel bearing/hub lateral runout. 4. Wheel mating interface has been overtightened (did not follow WIS torque procedures). 5. Mating interfaces have been excessively modified (painted, gouged, bent, etc...). Remedy Read through the entire attached worksheet prior to performing. After performing, please review the final page and perform work accordingly. NOTE: This document is not pre‑authorization or otherwise dealing with warranty. This is intended for diagnostic purposes only. If there are any questions on how to proceed OR The work sheet has been performed and the vehicle has returned with the same concern. Please perform the measurements as seen in the worksheet again and open a TIPS case to the Body, Chassis, and Entertainment team.

Complaint Only vehicles with a variable transfer case are affected. This can be identified through control unit N45 or N15/7 in the quick test. When accelerating with light load, vibrations or jolting sensation may come from the drivetrain. It may be mistaken for a harsh shift. Cause Modified oil quality of the transfer case over time Remedy 1. Check initial quick test for faults in the following control units. N45 or N15/7 ‑ All‑wheel drive (ARS) N127 ‑ 'Drivetrain' (PTCU) control unit Y3/8 ‑ Transmission control for 9‑gear transmission (VGS) N3/10 ‑ Engine electronics for combustion engine If faults are present: Process them as per the guided test in Xentry. If no faults are present: 2. Check the transmission oil level If the oil level is correct: 3. Unplug the connector for the transfer cases control unit and reassess the vehicle on a subsequent test drive If the complaint no longer occurs with the control unit disconnected: 4. Perform an oil change of the transfer case according to WIS specifications ‑ Collect an oil sample of the original fluid 5. Complete all transfer case Tech‑in processes located under VG Control Unit > Adaptations ‑ Resetting the oil service data ‑ Calibration of N15/7 5. Perform road test of vehicle to bring transmission to operating temperature (>60C ) 6. Operate vehicle in full circle with steering at full lock ‑ 5x to the left ‑ 5x to the right Return the vehicle to the client and request they drive the vehicle for at least 200 miles and return if the concern is not resolved. The extended drive will ensure the clutches are properly conditioned with the new oil and should resolve the concern. If this LI has already been applied to the vehicle, please submit a TIPS case to the Powertrain inbox with the following information: ‑ Initial quick test with fault freeze frame data ‑ Initial transmission EEPROM data ‑ VGS and Transfer Case Control Unit Log (N45 or N15/7) ‑ Special Acquisition Data .txt file (Transfer Case Control Unit > Special Procedures > Procedures for support queries to market support > Special Data Acquisition) ‑ Photo of the original oil condition ‑ What color was the fluid drained from the transfer case before the oil change? ‑ Was an oil sample collected, and can you provide a photo of the original fluid? ‑ What color and part number fluid was used during the oil change? ‑ How far was the vehicle driven after?

Complaint Clanking noise from the area of the speakers in the doors. Cause Under analysis. Remedy To narrow down the cause, first of all remove the door trim. • If the noise continues to occur even with the door trim removed, then continue the diagnosis working towards the speaker and if necessary, create a TIPS case with an informative video as an attachment. Note: Please refer to this document in the warranty claim and, once diagnosis is completed, select the damage code depending on the component part that is causing the issue. • If the noise stops when the door trim is removed, please proceed in accordance with LI72.10‑P‑067691. Information: In this case, do not use a damage code for the speakers in the warranty claim!

Complaint Noises/ squealing from the service brake in various driving situations and ambient conditions. Cause Frictional vibrations Remedy The intent of this document is to reduce noise from high performance AMG brakes. AMG brakes are designed for performance under high load and in certain scenarios, can emit noise. Some scenarios are normal and some are induced by driving style like those listed below: • Driving style such as two footed driving where the pad might be in constant contact with the rotor. • Brake pressure and application style (stop‑and‑go traffic with consistent light brake pressure “riding brakes” where the brakes cannot cool sufficiently between applications). This can cause the brake pads to glaze and have a smooth/glassy surface which can induce noise. • When ambient temperatures rise during summer peak and during cooling and cold winter months. 1. Beginning Diagnostics: a) Check whether the complaint can be reproduced and at which axle or side the noises occur (ideally together with the customer while driving). b) Check the affected system for component wear, mechanical damage or localized overheating damage. Replace damaged components as necessary. c) Assess condition of brake rotors and pads per WIS and visually (i.e. long periods of stagnation, etc...). d) Clean brake components free of brake dust and debris. d) Secure vehicle on a lift. 1. Start the engine and depress the brake pedal 3‑4 times. 2. Check each wheel to see if they turn freely by hand. 3. If a wheel is not turning freely by hand, this needs to be addressed prior to re‑assessing the noise concern. e) Check whether, apart from this document, an additional document exists for the specific model in question, and if so, work through it and then continue. 2. Specific Axle Work: NOTE: If the brake pad has a metal backing plate, there is no need to affix the adhesive film. Continue with applying chamfer and Molykote as instructed below. IMPORTANT: Be absolutely certain to not allow paste between friction surfaces of the pad and disc! a) If the noises are coming from the front axle. 1. Remove brake linings of front axle. 2. Clean all contact points on brake lining backing plate, including the brake lining guide pins and brake caliper/carrier. 3. Clean bonding surface (where pistons contact back of brake pad). Apply adhesive film to the backplate of the piston‑side brake lining where the piston contacts the pad backing plate. See picture "Adhesive and Paste Application Area". 4. Be sure to remove both brown paper backing sides of the adhesive film, it is double sided adhesive film. 5. If adhesive is already installed on backing plate where pistons contact the back of the pad, you may gently scrape off and re‑apply a new adhesive or Molykote. Must not apply the Molykote on top of the adhesive. 6. Chamfer edges (gently round off sharp leading edges) on brake pads. Some pads have vertical grooves, these can be gently chamfered with a triangular file as well. See picture "Chamfering Technique". 7. Apply Molykote to the sides of the backing plate. See picture "Adhesive and Paste Application Area". 8. After installing the brake linings, actuate the brake for 30 seconds. b) If the noises are coming from the rear axle. 1. Remove brake pads of rear axle. 2. Clean all contact points on brake lining backing plate and brake caliper /carrier. 3. Clean bonding surface (where pistons contact back of brake pad). Apply adhesive film to the backplate of the piston‑side brake lining. 4. Chamfer edges (round off sharp leading edges) on brake pads. See picture "Chamfering Technique". 5. Grease contact points (red areas on attachment "Rear Pad Grease Area") between brake lining and guide of brake caliper with Molykote. 3. Brake Bedding Process: a) Before trip, the mileage incurred must be clarified with the customer (approx. 30 miles). b) Select a suitable route so speeds of approximately 65 MPH can be achieved. c) If the vehicle is an AMG P3 Hybrid, switch off

Complaint During part of the steering movement, it feels heavier or more difficult to steer in the same spot every time. OR Rattling, humming, dry sliding/gravel noise from the electric steering system when steering (see attachment). Complaint does not impact the ability to safely steer or control the vehicle. Cause Ball screw drive (KGT) of electric steering damaged by: 1. External force due to: ‑ Hitting the curb/posts with the front wheels. ‑ Driving over obstacles (e.g. pothole/ threshold/ speed bump/ gully) at an inappropriate speed. 2. Corrosion/ water ingress through a damaged boot (see attachment). ‑ Cracks (1) ‑ High pressure cleaner (2) ‑ Animal bite (3) See various examples listed in the attachments for examples of outside influence. Remedy Remove boot clamps closest to steering gear housing on both left and right (as seen in "Steering Rack Boot Clamp Location"). Pull back boot and inspect for rust, broken end stops, water, or any other anomalies. Replace electric steering. Note: Steering gears replaced due to outside influence or damage must not be claimed under warranty!

Complaint Tailgate opens unintentionally. Cause Accidental or unnoticed activation of the button to open the tailgate on the vehicle key. EXAMPLE: when stored in trouser pocket, handbag etc. Remedy As of the 6th generation, the vehicle key can be recoded so that the tailgate no longer opens as a result of a long press on the button, but by double‑clicking on the button instead. This reduces the likelihood of the button being activated accidentally or unintentionally. The recoding can be carried out as follows: 1. Add SA Code O19 into VeDoc (O for Oscar, not "zero") • an XSS ticket may be necessary to add the SA code 2. Perform SCN coding of EIS N73 control unit 3. Deactivate the vehicle key (a successful deactivation is indicated by the LED lighting up 2x briefly and then 1x for a long period). 4. Place the vehicle key in the storage compartment on the key symbol and turn on the ignition. IMPORTANT: all other vehicle keys must be outside the recognition range of the vehicle when doing this! Perform steps 3 and 4 successively for all vehicle keys. Notes: 6th, 7th and 8th generation keys can be deactivated as follows: Up to modification year 22/1 by double clicking the "Lock button" As of modification year 22/1, by press and holding the “Lock button", then double‑click the “Unlock button" at the same time. On model series 167, the storage compartment with the key symbol is located in the armrest. The SCN coding from the EZS is only transferred correctly to the vehicle key under the following conditions: Only one vehicle key is located in the vehicle, this key has been deactivated and it is positioned on the marking in the storage compartment for the data transfer. The costs for this adaptation are to be borne by the customer. For the newer BR 174, 178, 244, 248, 520, and 540, a software update must be initiated, as there is no way to perform SCN coding.