2021 Mercedes-Benz Eqc 400 E

Service bulletins

Technical service bulletins and other communications the manufacturer sent dealers about this vehicle. Ask a dealer for the full document by its number.

• 11009122Complaint Washer fluid system leaks Cause Various possible causes: 1. Washer fluid reservoir itself. 2. Seal on washer fluid pump/washer fluid reservoir. 3. Washer fluid pump. 3.1. Distributor housing leaks. 3.2. Pump fitting leaks. 3.3. Washer fluid hose cannot be snapped into place on pump fitting. 3.4. Washer fluid hose will not stay on pump fitting, although connector OK. 4. Washer fluid line. 4.1 Connector will not stay on pump fitting because it is broken. 4.2 Sealing ring in connector missing. 4.3 Sealing ring in connector fitted, but deformed and therefore leaks. 4.4 Damage to washer line by animal. 5. Seal on heating washer fluid reservoir/washer fluid reservoir. Remedy Replace defective component parts only. Do not replace any adjacent component parts that are intact. Note: Repair kits for washer line hoses do exist to allow patches for line damage.
• 11008091Complaint 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) in the headliner. C. Dirt inside the microphone housing Remedy 1. Press finger on rear of microphone (on adhesive tape) 2. Remove microphone cap from the front 3. Eliminate protruding material residues of the microphone cutout at the headliner, e.g. with a soldering iron. The microphone must be seated in the headliner as shown in picture "2". 4. Push microphone from behind until it is firmly pressed into the headliner 5. Maintain pressure and press/clip cap into microphone from the front. Note: The cover cap must be clearly heard and felt to engage. 6. This procedure must be carried out on both microphones (B25/20 and B25/21) Note: It is recommended to replace the cover caps. The non-woven cloth in the cover cap protects the microphone from soiling and must not be removed. NOTE: The information contained in this document is intended for use by trained, professional technicians with the knowledge to properly and safely perform diagnosis and repairs on Mercedes-Benz vehicles, using Mercedes-Benz approved tools and equipment. It informs service technicians about conditions that could occur in certain vehicles and provides information that could assist in proper vehicle diagnosis, service, or repair. It does not indicate that a defect is present in any vehicle referenced in this document nor does it imply warranty coverage. DO NOT assume that a symptom or condition, or a described cause of a symptom or condition, affects any particular vehicle or groups of vehicles, or that a described repair applies to any particular vehicle or groups of vehicles. There can be multiple causes resulting in the same or similar symptoms or conditions described in this document, and trained professional service technicians must use their diagnostic skills to make evaluations on a case-by-case basis. The information contained in this document does not guarantee warranty coverage nor does it extend the vehicles warranty in any way.
• 11007974Complaint 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 In advance, observe LI82.10-P-078301 "Headlamps or Front Fog Lamps Leaking or Fogged". 1. Prepare headlamp/check for external damage: For headlamps with a closed system 1. Check the headlamps for any external damage and check also for correct seating of the Gore-diaphragm/correct latching of the cover caps. 2. If the headlamp exhibits any external damage, replace the headlamp. For headlamps with an open system 1. Check the headlamps for any external damage and seal off the vent then make sure the cover caps are latched correctly into place. 2. If the headlamp exhibits any external damage, replace the headlamp. Note: A headlamp with external damage is not a warranty or goodwill case. 2. Leak test of headlamp with overpressure: Connect test adapter to pressure tester. (Figure 1) Check test adapter for leak tightness. To do so, connect plug and coupling (picture 2) and apply a maximum overpressure of 30 mbar. The pressure must remain constant. If the pressure does not remain constant, use a new adapter. Seal all the outlet openings using sealing compound and the given diaphragm with the plunger (picture 3). (Picture 4) Make allowance for the different headlamp variants here (there are different outlet openings). Check if the headlamp needs to be removed to gain access to the diagnostic socket on the headlamp housing. Plug the adapter onto the diagnostic socket on the headlamp housing. (Picture 5). Apply a maximum of 30 mbar overpressure to the headlamp housing. Note: If the maximum overpressure of 50 mbar is exceeded the headlamp seal will be damaged. If a pressure drop of less than 10 mbar is measured within 30 seconds, the headlamp is not leaky and the problem is down to natural physical fogging. If a pressure drop of more than 10 mbar is measured within 30 seconds, the headlamp is leaky. Note: The leaky position can be localized with the aid of soap suds. Replace any leaky headlamps. Note: Desiccant packs can be installed for headlamps that are not leaky. See: LI82.10-P-064766 Fogged headlamp, desiccant pack installed - open ventilation system LI82.10-P-078304 Fogged headlamp, desiccant pack installed - closed ventilation system
• 11007753Complaint Headlamp or 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. Headlamps comply with all applicable standards. If a pressure compensation diaphragm is fitted in the housing cover, then the lamp unit is a "closed system". Remedy Headlamp: Remedy 1 Clearing fogged/condensed LED headlamps and LED rear lamps: 1. Drive vehicle into workshop (temperature higher than +18 C/+64.4 F) and connect the exhaust extraction. Note: Do not perform an engine wash before the defogging test. 2. Switch off the engine and connect battery support via a charger. 3. Open the hood or trunk. 4. Switch on the lights. 5. Leave the vehicle in this state for 60 minutes. 6. Check for formation of condensation, a significant reduction in the formation of condensation must be clearly recognizable (thawing progress). Clearing fogged/condensed halogen/xenon headlamps: 1. Drive the vehicle into the workshop (temperature higher than +18 C/+64.4F). Note: Do not perform an engine wash before the defogging test. 2. Switch off the engine. 3. Open the hood. 4. Switch off the lights. 5. Leave the vehicle in this state for 60 minutes. 6. Check for formation of condensation, a significant reduction in the formation of condensation must be clearly recognizable (thawing progress). Note: If there is no visible reduction in the formation of condensation, check the headlamp for a defect. (See Remedy 2) It is not physically possible to defog the headlamps completely. Fogging does not impair the operation or the service life of the headlamp. Remedy 2 A Damaged headlamp can be identified as follows: 1. Check the headlamp for external damage and that the cover caps and the diaphragm are correctly seated. 2. Check the electrical connectors of the plugs and pins. 3. Check for leak tightness in accordance with LI82.10-P-078307. The test can only be conducted on headlamps. 4. If the headlamp or the rear lamp has any external damage, replace the component part in accordance with the WIS instructions. Note: External damage to the headlamp/rear lamp or faulty seating of the cover caps does not present a warranty or goodwill case. With headlamps, it is possible to install desiccant packs if the problem occurs repeatedly. Open ventilation system: LI82.10-P-064766. Closed ventilation system LI82.10-P-078304
• 11005294Complaint Rear lamps fogged up/not leaktight. Cause Fogging of the rear lamps is a natural phenomenon, which can occur under certain climatic conditions. This does not lead to any technical impairment of the rear lamps. Remedy Rear lamp: Remedy 1: Clearing fogged/condensed rear lamps: 1. Drive the vehicle into the workshop (temperature higher than +18 C/+64.4 F) Note: Do not wash the vehicle or subject it to high-pressure cleaning before the defogging test. 2. Switch off the engine and connect battery support via a charger. 3. Open the trunk. 4. Switch on the exterior lighting. 5. Leave the vehicle in this state for 60 minutes. 6. Check for formation of condensation -> a significant reduction in the formation of condensation must be clearly recognizable (defogging progress).
• 11003205Complaint The driver's seat memory settings do not synchronize with the driver's user profile as described in the operator's manual. Driver's seat settings are not transferred to the vehicle. Cause The driver's seat does not support the profile synchronization feature on these vehicles. Remedy There is no remedy for this complaint. The vehicle is working as designed. Note: Do not replace any parts.
• 10249495Noises in the steering column area when steering. Under analysis. Check which area of the steering column the noises occur in. Do the noises tend to occur at the bottom in the driver footwell or do they tend to occur in the area of the steering column switch module (MRSM/SCCM)? If the noises occur in the area of the MRSM/SCCM, work through the following points: - Loosen screws of the MRSM/SCCM and steering wheel, re-align the MRSM/SCCM, and re-fasten the screws (see WIS). Sometimes there is stress at the MRSM/SCCM and noises occur. - If noises continue to occur, swap the MRSM/SCCM into a vehicle without any (noise) complaints. - If the noises occur with the MRSM/SCCM complained about when it is in the vehicle without a complaint (donor vehicle), the MRSM/SCCM can be replaced. - If noises also occur in the customer vehicle with the MRSM/SCCM from the reference vehicle, the MRSM/SCCM is not the cause and must not be replaced. Notes: - When installing the MRSM/SCCM, make sure that no damage occurs! - Only disassemble and mount all component parts in the "straight-ahead position" (see also WIS). - Please refer to this LI in the "Notes" section of the warranty claim!
• 10248162Crease formation on genuine leather seat covers in vehicles with low mileage Objects left on the seats for extended periods of time (pressure marks). Objects wedged between the seat backrest and seat cushion (e.g. seat belt buckle). Light initial creases due to vehicle handling. Light creases in the outer covers originating from the production process (missing finish). Heat treatment of the seat covers using heat gun and plastic wedge. Be very careful to not overheat the seat material!
• 10244837The "SOS nonfunctional" message appears sporadically in the instrument cluster of the vehicle. The fault code B129C00 is stored in the control unit log. The message occurs in particular after the vehicle has been non-operational for an extended period of time; the message then disappears of its own accord after a few minutes. No functional limitation to the emergency call system is to be expected. Software error in N112/9 control unit for telematics services (HERMES). Software update for control unit N112/9 - Control unit for telematics services (HERMES) to software release E522.8. If, against expectations, the erroneous display of the message in the instrument cluster continues to occur following the update, please create a TIPS case.
• 10231032Complaint 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.
• 10228807Complaint Height adjustment of electric steering column adjustment jammed in the top/bottom adjustment position (e.g. with Easy Entry function). Cause Height adjustment moves to the top/bottom limit stop and jams.
• 10227142Complaint 1. Vibrations noticeable at steering wheel when front axle is excited when driving at a speed between 65 km/h and 130 km/h over an obstacle. Driving over deeply recessed manhole covers Driving over cross joints Driving over extreme surface undulations 2. Permanent or long-lasting vibrations at specific speed or engine speed noticeable on steering wheel. Roadway surface excitations when DTR+Q is switched on Cause Control oscillations in the electric power steering
• 10206077"MY15+ M278 and M157 Equipped Vehicles with Fault Code ""P023400 Boost Pressure is Too High"" "
• 10205840Mounting support could be cracked.
• 10205154Gasket may settle causing a slight oil leak.
• 10199449Launch NCU - 2021030010 MY20-21 Various Add Supplementary Booklet to Printed Operators Manual
• 10186135If the customer brakes sharply from a speed of > 30mph, without ABS intervention, there is a single cracking noise from the area of the ESP hydraulic unit