2020 Mercedes-Benz AMG GLB35

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’).

Complaint Hand detection system – malfunction / vehicles with code 266 Fault message in instrument cluster: "Active Emergency Stop Assist not available" "Active Lane Keeping Assist not available" "Active steering assist not available" Cause Possible causes: Hand detection mat, hand detection control unit, contacts, and electrical feed line. Remedy In the event of a customer complaint and fault code in IDC control unit: U186B29 in IDC223 or fault code U0429E0, U042941, U042929, U042902, U0429E1 in IDC213 or fault code in HOSWD control unit: B1E7614 Check: Please do not replace the HOSWD control unit. Please flash the new SW and perform the SCN coding for the HOSWD control unit (N179/1) (available from July 2026). The software can be flashed onto all HOSWD213 with HW number A0009011522 and all HOSWD223 with HW number A0009011422. Please also flash the SW for the IDC control unit (N62/4), if possible (only applies to HOSWD223). Erase fault memory Remedy: Turn on the ignition or start the engine without touching the steering wheel. If, after 10 seconds without touching the steering wheel, one of the three fault messages appears on the instrument cluster: Check the contacts and feed lines in the steering wheel by means of a visual inspection for damage, crimp connections, loose connections, etc. (example in picture 2 and 3). If there is visible damage -> replace the steering wheel electronics or the feed lines. If there is not any visible damage -> replace the steering wheel rim. If a yellow message does not appear on the instrument cluster within 10 seconds: Grasp the steering wheel fully with both hands, including the chrome molding at the 6 o'clock position (see picture 1). If the fault is triggered by grasping the steering wheel rim or pressing the clip at the 6 o'clock position, check the contacts and feed lines in the steering wheel by means of a visual inspection for damage, kinked connections, loose connections, etc. (example in picture 2 and 3). Check the ground connections (screw connections and cables to the steering wheel rim); if necessary, retighten the screws/bolts and check for corrosion (picture 4). If there is visible damage -> replace the steering wheel electronics or the feed lines. If there is not any visible damage: Replace the steering wheel rim. Please do not replace the HOSWD control unit. A TIPS case should be created if fault profile is unclear. In the event of a customer complaint and a further fault code in HOSWD: B1E7713: Check the ground connections (screw connections and cables to the steering wheel rim); if necessary, retighten the screws/bolts and check for corrosion (picture 4). B1F1F04: Check the control unit of the hand detection system; if necessary, replace this with the control unit from a donor vehicle (make sure that the hardware part numbers are identical).

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).

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. Cause Information only Remedy Acronyms: • AV = Actual Values • CPR = Car Package Release (For MB.OS) • CU = Control Unit • CUL = Control Unit Log • DTC = Diagnostic Trouble Code • E-Stand = Fresh-up head unit boot software (found in head unit control unit log) • FUP = Fresh-up • FW = Firmware • HSVL = High Speed Video Line • HU = Head Unit • HW = Hardware • IPD = Injector Performance Data • ISU = Initial Start Up • LVDS = Low Voltage Differential Signal • NAG"x" = New Automatic Gearbox ("x" is the generation number, example: NAG3) • NSFT = Not Safe For Transport • MOPF = Model Facelift (Ex: 167 MOPF) • PiH = Plug-in Hybrid • SA Code = Sonderausstattungscode (Option Code) • SCN = Software Calibration Number • SW = Software • TCU = Telecommunication Control Unit (Hermes/Ramses/Etc...) • QT = Quicktest • XD = XENTRY Diagnosis Control Unit Identification: Refer to the attachment "Control Unit Nomenclature" for location of each. • Control Unit Name • Control Unit Number • Control Unit Short name • Control Unit Diogenes ("dy-oj-uh-neez") name - Control unit variant/family. Network/Wiring Architecture to Baumuster Quick Reference: Star 1 • 117, 156, 246 (MFA) • 166, 176, 221, 242, 246, 292 • 906 Star 2 • 205, 213, 238, 253, 257, 290 (MRA) • 117, 156, 246 (MFA) • 118, 177, 243, 247 (MFA2) • 167, 222, 292, 463, 465 • 907 Star 3 • 294, 295, 296, 297 (EVA2) • 206, 214, 223, 236, 254 (MRA2) • 192 and 232 (MSA) Star 3.5 • 174 • 178 Platform to Baumuster Quick Reference: MRA = "Mercedes-Benz Rearwheel Architecture": • 205 • 213 • 222 • 238 • 253 • 257 • 290 MRA2 = "Mercedes-Benz Rearwheel Architecture - Generation 2": • 206 • 214 • 223 • 236 • 254 MFA = "Mercedes-Benz Frontwheel Architecture" • 117 • 156 • 246 MFA2 = "Mercedes-Benz Frontwheel Architecture - Generation 2" • 118 • 177 • 243 • 247 EVA1.5 = "Electric Vehicle Architecture" • 243 EVA2 = "Electric Vehicle Architecture - Generation 2" • 294 • 295 • 296 • 297 MSA = "Mercedes-Benz Sport Architecture" • 192 • 232 MMA = "Mercedes-Benz Modular Architecture" • 174 • 178

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. 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: 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. 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 of fogged/condensed LED headlamps and LED rear lamps on electric vehicles: 1. Drive the vehicle into the workshop (temperature higher than +18 °C/+64.4°F). 2. Connect battery backup via a charger. 3. Open the front-end flap and ensure sufficient ventilation. 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/+64.4°F). 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 condensation, check the headlamp for malfunctions. (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. Note: Only implement Remedy 1 for model series 463 (from model year 2018) and model series 465. Remedy 2 A defective 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 according to 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. Note: With headlamps, it is possible to install desiccant packs if the problem occurs repeatedly. • Open ventilation system LI82.10-P-078302 • Closed ventilation system LI82.10-P-078304

Complaint -Check engine light illuminated. -Engine runs rough. -Poor shifting or jerking when accelerating. -Fault codes stored related to mixture formation, injector quantity adjustment, or misfire. Note: One or more of the above symptoms can occur. It is possible that no fault codes are stored. Cause Leaking valve seat in cylinder head. Remedy -Perform cylinder leakage check as noted in WIS group 01.00. If excessive leakage is found determine if leak is from intake or exhaust valves. -If leakage is found from intake or exhaust valves, remove cylinder head and inspect valve seats. -The complete cylinder head must be replaced if valve seat damage is found. The valve seats can not be reworked. -Engine oil and filter should be changed after the repair. Workshop notes cylinder head repair: 1. The intake rocker arm roller is narrower than the exhaust and they must not be interchanged. Mark the rocker arms so they are reinstalled in their original location. 2. Inspect all parts that are being reused (i.e. camshafts, rocker arms) for signs of wear or damage. See WIS doc AH05.20-P-1000-09SZ for examples of normal and abnormal wear. Replace parts with new if damage or wear is found. 3. Check that all rocker arms are correctly located on the camshaft before installing cylinder head cover. Rotate engine at least 2 times and check that there are no problems with rocker arms. 4. The timing chain tensioner can be reused if it extends fully, has no noticeable problems in prior operation, and no chain drive components were replaced. 5. Care must be taken when removing fuel injectors to prevent damage. See WIS doc AR07.03-P-0004-03MM. 6. Cleanliness must be observed during repair to prevent subsequent complaint or engine damage: • When cleaning engine block surface, ensure oil ports are sealed to prevent debris from entering oil circuit. Refer to SI01.40-P-0010A. • No abrasive materials, sharp-edged tools, or unapproved cleaners should be used on engine block surface. Refer to AR01.00-P-0050-01A. • Any debris from cleaning that has entered the cooling jacket should be removed before assembly of engine. The debris can otherwise cause blockage in the cooling circuit leading to engine overheating. If any of the parts listed below are found damaged or in need of replacement during cylinder head valve‑seat diagnosis or repair, and the vehicle has warranty coverage, they must be claimed on a separate parts‑only line. These items are not covered under the cylinder head warranty extension and cannot be included with the claim. • Camshafts • Camshaft adjustment solenoids • Camshaft positioners • Fuel injectors • Hydraulic valve play compensating elements • Roller rocker arms • Spark plugs • Timing chain • Timing chain guide rails