2021 Mercedes-Benz AMG GLA35

The contact owns a 2021 Mercedes-Benz GLA250W4. The contact stated that while parking his vehicle when he went to apply the brake pedal, the brakes did not engage. The contact stated that the vehicle then crashed into the wall, however, the air bags did not deploy. The contact stated that the warning light illuminated after the crash indicating that "the brakes are now operational". The contact stated that there was no police report made, however, the 2 passengers did seek medical attention. The contact stated he was able to drive his vehicle home, however, the dealer did have the car towed days later and it remains for repair. The contact stated the dealer advised him to contact the manufacturer, as he did to file a complaint. The failure mileage was 9,429.

NHTSA ID

11462756

Incident

Apr 23, 2022

Mileage

9,429 mi

Complaint • While driving, engine speed may increase with accelerator pedal input while vehicle acceleration remains limited with no torque transfer to the wheels • 4th gear may remain displayed in the instrument cluster after the condition occurs, including when the vehicle has come to a standstill. • Cycling the ignition may restore normal transmission operation. • No related fault code or warning message may be stored. Cause During extended periods of steady driving in 4th gear, a preventative flushing routine of the Mux2P valve may be performed in the transmission valve body. If 3rd gear is requested shortly afterward, the pressure within the Mux2P oil channel may not yet have fully reduced. Under these conditions, the transmission control unit may detect an implausible shift actuator movement. As a protective measure, the transmission control unit may temporarily shift the transmission into neutral. As a result, 4th gear may continue to be displayed in the instrument cluster even after the vehicle has come to a standstill. Remedy Please perform the following: 1. Update software TCM8FDCT_PT4 transmission control unit

Complaint • While driving, engine speed may increase with accelerator pedal input while vehicle acceleration remains limited with no torque transfer to the wheels • 4th gear may remain displayed in the instrument cluster after the condition occurs, including when the vehicle has come to a standstill. • Cycling the ignition may restore normal transmission operation. • No related fault code or warning message may be stored. Cause During extended periods of steady driving in 4th gear, a preventative flushing routine of the Mux2P valve may be performed in the transmission valve body. If 3rd gear is requested shortly afterward, the pressure within the Mux2P oil channel may not yet have fully reduced. Under these conditions, the transmission control unit may detect an implausible shift actuator movement. As a protective measure, the transmission control unit may temporarily shift the transmission into neutral. As a result, 4th gear may continue to be displayed in the instrument cluster even after the vehicle has come to a standstill. Remedy Please perform the following: 1. Update software TCM8FDCT_PT4 transmission control unit

Complaint Slight creaking noises when steering. Cause Noises may come from one or more sleeves of the horn contact plate. Remedy Remove the horn contact plate and check the sleeves for noise; see attached video. If necessary, apply lubricant to the sleeves.

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 Radio station cover art does not refresh when switching stations. The UI continues to show the old station’s artwork instead of updating to the new one. Cause When a new station change request is triggered, a temporary glitch is causing the Head Unit application to fail to overwrite the previous request. This glitch is causing the cover art mismatch in the Radio application. Remedy Please do not replace any parts. Please update the Head unit software to E505.9

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!