2021 Mercedes-Benz E 450 Technical Service Bulletins

239 technical service bulletins (TSBs) are on record for the 2021 Mercedes-Benz E 450. TSBs are notes manufacturers send to dealers about repair procedures for issues seen in the field. They are not recalls and do not by themselves mean a vehicle has a fault.

• 11026833Dec 20, 2025Transmission and drivetrain. Complaint (Original LI document #: LI27.35-P-079039) Clicking noises from the electro-hydraulic control unit (EHS) when the vehicle is stationary and ECO Start/Stop is active (combustion engine is off). The noise is more noticeable outside the vehicle and in acoustically shielded areas such as closed rooms or garages. Cause The noise in the valve body (EHS) is caused by superimposed pressure peaks acting on the…
• 11026596Dec 6, 2025Suspension, Electrical system, Engine. Complaint <p>ESP®, BAS, PRE-SAFE®, HOLD function, Hill-Start Assist, ESP® trailer stabilization, Adaptive Brake Lights, Lane Keeping Assist, Blind Spot Assist, Adaptive Brake Assist, and/or ATTENTION ASSIST may be temporarily unavailable. The brake system continues to operate with normal effectiveness.
• 11025560Nov 17, 2025Transmission and drivetrain. Complaint The shift from 1st to 2nd gear may be uncomfortable under light load. Cause Vehicles with engine M264 and transmission 725.0 may be equipped with specific software versions. Remedy Update Transmission Software (VGSNAG3). 1.
• 11025648Nov 15, 2025Transmission and drivetrain. Complaint Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end). The clunk is heard once when changing from forward to reverse (and vice versa). 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 micromovement in the connection between the wheel bearing inner…
• 11025471Nov 10, 2025Transmission and drivetrain. Complaint Possible complaints about shift quality, issues with learning the park lock, and slipping/rinse entries in the EEPROM or Transmission Health system following the replacement of the below components: - The electrohydraulic control unit (EHS valve body) in transmission 725.0/725.1 - The repair kit for the control unit (VGS) in transmission 725.0 Cause Missing, incorrectly installed, or damaged guide tubes…
• 11025100Nov 3, 2025Transmission and drivetrain. 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.
• 11024405Oct 20, 2025Brakes. Complaint At low speeds and light brake pressure, brakes will make a groaning or honking noise. Cause Frictional vibrations with very light brake pressure/modulations. Remedy This condition can be duplicated on most vehicles. To validate, use a like for like reference vehicle. The noise is normal behavior under the conditions listed. With very light brake pressure this noise can be induced/caused due to normal…
• 11024224Oct 11, 2025Electrical system. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the engine control unit software does not correspond to current production specifications. As a consequence, the functionality of the post-catalyst oxygen sensor may be impaired due to increased thermal loading. MBUSA will conduct a service campaign. An authorized Mercedes-Benz dealer will update the…
• 11023347Sep 25, 2025Electrical system. Complaint The result from the XENTRY battery test does not match the current state of the battery. Cause The XENTRY battery tester uses the stored on-board electrical system data in the SAM module to access the health of the 12 volt battery. The XENTRY battery test may not take into account a single discharge event because the SAM or EZS cannot record the data if the battery is discharged. Note: A discharged…
• 11023264Sep 19, 2025Electrical system. See Attachment
• 11023193Sep 17, 2025Transmission and drivetrain. Complaint Transmission control unit Y3/8n4 (fully integrated transmission control unit (VGS)) not listed in quick test and/or no communication possible with VGS. Cause Transmission control unit Y3/8n4 Remedy For vehicles with 722.9 transmission: Ensure LI54.15-P-057373 is performed before replacing any component parts. After processing and complying with the above document(s): 1. Perform an ignition reset on Y3/8n4…
• 11023194Sep 16, 2025Electrical system. Complaint After a software update from campaign 2025050001 of component LIB48_222 - G1/3 (48 V on-board electrical system battery) from software release A 000 902 50 48 to software release A 000 902 15 89, the fault code B183319 may be output. B183319 "The battery for the 48V on-board electrical system has a malfunction.
• 11023103Sep 11, 2025Electrical system. Complaint After a software update of component LIB48_222 - G1/3 (48 V on-board electrical system battery) from software release A 000 902 50 48 to software release A 000 902 15 89, the fault code B183319 may be output. B183319 "The battery for the 48V on-board electrical system has a malfunction.
• 11022442Aug 29, 2025Electrical system. Complaint Users report that the browser no longer supports search queries entered directly into the address bar. Cause This update is due to Microsoft discontinuing the Bing Search API, which previously supported this feature. Remedy This behavior is considered consistent with current system design and reflects the intended functionality. No corrective action is required.
• 11021108Jul 25, 2025Suspension. Complaint Creaking noise, in irregular sequence when driving slowly in combination with slight steering movements and/or Creaking/crackling noises from the area of the wheel bearing on the front axle when cornering/ maneuvering. Sound file attached for comparison. MUST match noise for proper diagnosis. NOTE: Steering functionality is not affected. Cause Contact area between wheel bearing and steering knuckle.
• 11020950Jul 18, 2025Electrical system. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the 48V battery control unit software might not meet current production specifications. In rare cases, the engine malfunction indicator lamp might not illuminate when a diagnostic fault condition is present. MBUSA will conduct a service campaign. An authorized Mercedes-Benz dealer will update the 48V…
• 11020875Jul 18, 2025Electrical system. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the 48V battery control unit software might not meet current production specifications. In rare cases, the engine malfunction indicator lamp might not illuminate when a diagnostic fault condition is present. MBUSA will conduct a service campaign. An authorized Mercedes-Benz dealer will update the 48V…
• 11020874Jul 18, 2025Visibility (wipers, defrost, mirrors). Complaint No cooling output, compressor inoperative. Cause Currently under analyzed. Remedy Please create a TIPS case and provide the following information: -Provide the refrigerant filling capacity -Current actual values from XENTRY (compressor values) -Has there previously been work on the refrigerant circuit in the vehicle? -Check air conditioning system for leak tightness as per WIS -Document results and…
• 11020675Jul 11, 2025Electrical system. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the MBUX system software does not correspond with the latest series production configuration. The MBUX system will receive an OTA update that includes general product improvements and robustness enhancements for the “Live Traffic Information” and “Point of Interest” (POI) features. MBUSA will conduct an…
• 11019782Jun 28, 2025Forward collision avoidance, Lane departure, Electrical system. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has updated driver assistance system SCN coding available for certain subject vehicles. The updated SCN coding improves system stability and enhances the availability of driver assistance features. MBUSA will conduct an OTA service campaign. Remote SCN coding updates are automatically downloaded and installed in the customer’s vehicle free of charge and…
• 11019747Jun 9, 2025Steering. Complaint Height adjustment of electric steering column adjustment jammed in the top/bottom adjustment position (e.g. with Easy Entry function), noise (breakaway noise) when leaving the limit stops of the height adjustment. Cause Height adjustment moves to the top/bottom limit stop and jams. 1. Driver seat control unit software 2.
• 11019016May 30, 2025Fuel system, Electrical system. In our continuing efforts to ensure the proper performance of Mercedes-Benz products and to enhance the satisfaction of our customers, Mercedes-Benz USA is extending the warranty coverage for the Diagnostic Module for Tank Leakage detection (“DMTL”) on your vehicle from the original New Vehicle Limited Warranty of 4 years / 50,000 miles to 15 years/150,000 miles (whichever occurs first). This applies to the vehicle…
• 11018712May 30, 2025Electrical system. Complaint MBUX head unit display with red text box "System Inoperative". ONLY for vehicles with SA code (549+21U) or (549+U19). Cause Head unit software variant. Remedy For all chassis use Xentry to update head unit (A26/17). Target boot software number should be either: • 247 904 6600 (E905.4) OR • 247 904 7500 (E906.1) If vehicle fits all criteria and either target software is not available via Xentry, please…
• 11018626May 22, 2025Electrical system. Complaint After a software update of HERMES communication module N112/9 has been performed on a gray import vehicle, the message "SOS - Service not activated" is displayed in the instrument cluster. Cause The message "SOS - Service not activated" tells the customer that "over-the-air" registration of the vehicle with the Mercedes Intelligent Cloud is not possible.
• 11019018May 21, 2025Transmission and drivetrain. Complaint Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end). The clunk is heard once when changing from forward to reverse (and vice versa). 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 micromovement in the connection between the wheel bearing inner…
• 11018211May 8, 2025Electrical system. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that certain Model Year (“MY”) 2019 – 2022 C-Class, CLS, E-Class, E-Class Coupe/Convertible, GLE/GLS-Class and AMG GT vehicles (206, 257, 213, 238,167 and 290 platforms) are potentially affected with multiple topics related to the 48V battery management system, which erroneously may or may not illuminate the check engine malfunction…
• 11018164May 7, 2025Electrical system. Complaint Please note that the exact quick test conditions must be met as seen below. If not exactly as listed below, there is no need to create a TIPS case referencing this LI unless further assistance is needed outside of this document.
• 11018206May 2, 2025Electrical system. Complaint The result from the XENTRY battery test does not match the current state of the battery. Cause The XENTRY battery tester uses the stored on-board electrical system data in the SAM module to access the health of the 12 volt battery. The XENTRY battery test may not take into account a single discharge event because the SAM or EZS cannot record the data if the battery is discharged. Note: A discharged…
• 11018204May 2, 2025Forward collision avoidance, Steering, Lane departure. Complaint Hand detection system not operating correctly / vehicles with code 266 Fault message in instrument cluster: "Active Emergency Stop Assist not available" "Active Lane Keeping Assist not available" Cause Possible causes: the hand detection mat, the hand detection control unit, the contacts and the steering wheel harness.
• 11017500Apr 28, 2025Exterior lighting. Complaint Headlamps leaking or fogged Cause The fogging of the headlamp is a natural phenomenon which can occur under certain climatic conditions. In contrast to a leaky headlamp, physical fogging does not result in a technical impairment of the headlamp. A leak test must be performed to determine if physical fogging exists or if the headlamp is leaky. Remedy Check for external damage: You can identify a damaged…
• 11017496Apr 28, 2025Exterior lighting. Complaint Headlamp, front fog lamp leaky or fogged Cause Fogging of the headlamps is a natural phenomenon, which can occur under certain climatic conditions. It does not lead to any technical impairment of the headlamp. Remedy NOTE: If a pressure compensation diaphragm is fitted in the housing cover, then the lamp unit is a "closed system". Headlamp: Remedy 1 Clearing fogged/condensed LED headlamps and LED rear…
• 11017206Apr 21, 2025Exterior lighting, Electrical system. Complaint Instrument cluster message for rear turn signal lamp despite functioning rear lamp. Fault code in N10/8 - rear signal acquisition and actuation module in the quick test: B164B49 The rear right turn signal lamp has malfunctioned. There is an internal electrical fault. and/or B164A49 The rear left turn signal lamp has malfunctioned. There is an internal electrical fault. Cause Sensitive fault detection in…
• 11017119Apr 21, 2025Electrical system. Complaint A popup is seen on the HU with the message "data connection temporarily not available". Potentially affected functionalities in NTG4.5, NTG5 1.Weather 2.Local Search 3.IP Radio 4.Send2Car 5.Speech Detection Service 6.E-Navigator 7.iHeartRadio 8.Traffic Cams Cause Analysis ongoing. Remedy Please track the LI for further updates. Note: Please do not create TIPS cases. Please do not replace any components…
• 11017516Apr 11, 2025Steering, Electrical system. Complaint Hand detection system not operating correctly / vehicles with code 266 Fault message in instrument cluster: "Active Emergency Stop Assist not available" "Active Lane Keeping Assist not available" Cause Possible causes: the hand detection mat, the hand detection control unit, the contacts and the steering wheel harness. Remedy Test Procedure: Perform an initial quick test with freeze frame data.
• 11016221Mar 25, 2025Electrical system. Complaint This LI does Not apply to 223 or 206 which use a different generation of 48V systems. Please follow the relevant guided tests for the 223 and 206. For 223 with fault code B1FCB97 follow LI54.10-P-076026. Various causes are possible. The faults listed in the various causes do not all have to be present at all times. Some of these complaints may overlap. Rely on the faults listed in the Cause section for…
• 11016043Mar 24, 2025Transmission and drivetrain. Complaint A clicking/ticking/taping noise from underneath the vehicle with engine off during ECO stop event or after parking See video for example Cause Noise originates within the transmission valvebody Remedy Take a video from underneath vehicle recording the noise Pull EEPROM data, Inital Quick Test, and Control Unit Log Please open a TIPs case providing all data to assess next steps.
• 11015813Mar 18, 2025Back-over prevention (rear camera), Electrical system. Complaint MBUX headunit display with red text box "System Inoperative". ONLY for vehicles with SA code (549+21U) or (549+U19). Cause Under analysis. Remedy For chassis 118, 167, 177, 213, 238, 243, 247, 253, and 293 use Xentry to update headunit (A26/17). Target software number is 247 904 6600 (E905.4). If vehicle fits all criteria and target software is not available via Xentry, please open an XSS ticket.
• 11015574Mar 11, 2025Exterior lighting. Complaint The message "Device detected at diagnostics connection See Owner’s Manual" appears sporadically in the multifunction display of the instrument cluster while driving (see picture in attachment).
• 11015563Mar 11, 2025Visibility (wipers, defrost, mirrors). Complaint Rear side window reversed when opening/closing soft top - Convenience closing Cause 1. Rear side window setting 2. Damage to inner rear side window sealing rail (abrasion marks at sealing rail, see picture, folding of the sealing lip, see picture 2) 3. Body-in-white side wall shaft width too low. To this end, check the shaft width of the side wall for dimensional accuracy; see picture 3 Note: Inner and…
• 11015617Mar 10, 2025Body and structure, Electrical system. Complaint Tailgate opens unintentionally. Cause Accidental or unnoticed activation of the button to open the tailgate on the vehicle key. E.g. 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…
• 11015663Mar 7, 2025Electrical system. Issue Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the communication software does not correspond with the latest series production configuration. The communication module will receive an OTA update which includes quality-enhancing optimizations and improves the system stability and accessibility of Mercedes me services. The update is downloaded and…
• 11015659Mar 7, 2025Electrical system. Issue Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the communication software does not correspond with the latest series production configuration. The communication module will receive an OTA update which includes quality-enhancing optimizations and improves the system stability and accessibility of Mercedes me services. The update is downloaded and…
• 11015640Mar 5, 2025Electrical system. Complaint During a phone call, the called party has difficulty understanding/cannot understand the driver, or interference/background noises are audible to the called party during a call. It becomes increasingly difficult to understand as the speed rises. Cause A. Seating of the microphones in the headliner. Side edges are covered by the textile cover (see picture "1") B. Assembly of microphones (B25/20 or B25/21)…
• 11015545Mar 4, 2025Engine. Complaint Check engine light illuminated Fault code present in MRG3 control unit P22C800 or P22C900 - The valve of the exhaust gas turbocharger is jammed. Cause Check valve in charge air pipe jammed. Remedy Replaced charge air line with check valve.
• 11014610Feb 25, 2025Electrical system, Back-over prevention (rear camera). Complaint Please note that the exact quick test conditions must be met as seen below. If not exactly as listed below, there is no need to create a TIPS case referencing this LI unless further assistance is needed outside of this document.
• 11014402Feb 21, 2025Fuel system. Complaint Customer-perceived problem: • Fuel gauge reading implausible • MIL ON (market-dependent) N118/3 Fault codes in control units FSCM_GEN4/5/6 • For these fault codes, the tests contained in XENTRY must be carried out P046109 / P206609 / P13E600 • For these fault codes, the connector couplings/wiring harness routing must be checked for damage P206600 / P046100 Cause Various Remedy Carry out XENTRY tests for…
• 11014398Feb 20, 2025Other or unknown. Complaint The intent of this document is to provide workshops with helpful technical reference language. • Commonly used acronyms in LI's and TIPS cases. • Control unit names, numbers, and how to identify. • Network/wiring architecture groups to baumuster quick reference. • Platform to baumuster quick reference.
• 11014255Feb 12, 2025Visibility (wipers, defrost, mirrors), Electrical system. Complaint Please note that the exact quick test conditions must be met as seen below. If not exactly as listed below, there is no need to create a TIPS case referencing this LI unless further assistance is needed outside of this document. Conditions Instrument Cluster Message: "Park Assist Inoperative" and B223263 with Bosch-ID C259; A+S (Active and Stored) and B223255 with Bosch-ID 1B5D; A+S (Active and Stored)…
• 11014606Feb 7, 2025Electrical system. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain MY19-25 A-Class, C-Class, CLA, CLS, E-Class, G-Class, GLA, GLB, GLC, GT, and S-Class (118, 177, 205, 213, 217, 222, 238, 247, 253, 257, 290, 463 platform) vehicles, the communication software does not correspond with the latest series production configuration.
• 11014596Feb 7, 2025Electrical system. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain MY20-25 A-Class, C-Class, CLA, CLS, E-Class, EQB, GLB, GLE, GLS, AMG GT 4-Door, and S-Class (118, 167, 177, 205, 213, 222, 238, 243, 247, 257, 290 platform) vehicles, the communication software does not correspond with the latest series production configuration.

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