Service bulletins for the 2023 Mercedes-Benz AMG GT
A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.
185 on file from NHTSA, as of 2026-10-19.
By type
By component
By trouble code
By topic
| PSL-NCU Return Parts 6/19 | 2026-06-25. Other. VISIBILITY/WIPER; ENGINE. Dear Mercedes-Benz USA Dealers, The part numbers listed in the chart below should no longer be installed, and any existing stock must be returned to your facing PDC. The deadline for all dealer returns is no later than Thursday, July 9, 2026. After July 9th, returns of these parts will no longer be accepted. These parts should be returned via ZSR Special Return, using item category SCM Authorized Part Return. Please include a copy of this NCU as your authorization to return these parts. This procedure will not affect your return allowance. All returned parts will be replaced in accordance with the chart provided below. |
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| LI54.21-P-080326 | 2026-06-22. Service bulletin. ENGINE. Complaint CEL light on with no drivability concerns. Cause Signal timing error. Remedy 167: SW has been released. Update the FSAM to the latest SW version. 465, 290: Software is still in development. This fault code does not cause a drivability concern and will clear itself within 2-3 key cycles. The vehicle can be released back to the customer. |
| LI00.20-P-080703 | 2026-06-16. Service bulletin. ELECTRICAL SYSTEM. Complaint Service code B1 displayed in the customer menu does not match the workshop code displayed in the workshop menu, e.g., 505 or 550A, which includes a service A. Cause The root cause is currently being investigated. Remedy To determine the cause, the instrument cluster control unit (N133/1) and powertrain control unit (N127) logs are required before confirming the service or correction using XENTRY Diagnosis. Please open a TIPS case to BCE inbox with the requested information in the attachments. |
| LI00.20-P-077615 | 2026-06-16. Service bulletin. ELECTRICAL SYSTEM. Complaint 1. "Perform vehicle handover" in the workshop menu to start the maintenance computer for service A/B cannot be carried out. 2. Service confirmation is not possible because "Perform vehicle handover" is displayed. This cannot be carried out. 3. The service display in the instrument cluster permanently displays 365 days (remaining time) and does not change. Cause Routine change in the software in N133/1 (instrument cluster) or A26/17 (MBUX multimedia system and instrument cluster (head unit)). Vehicle handover was not performed. Remedy For model series 290 AMG up to and including AEJ 22 and model series 167 up to and including AEJ 21/2, the following applies: Manually commission already-installed instrument cluster control unit N133/1 and then perform special procedure to re-initialize ASSYST data in N127 powertrain control unit. For model series 167 as of AEJ 22/1, 192 AMG, 206, 214, 232 AMG, 236, 254, 290 AMG as of AEJ 23, 294, 295, 296, 297 and 465, the following applies: Reinitialize ASSYST Plus under Adaptations – Teach-in processes – ASSYST PLUS in control unit N133/1 (instrument cluster) or A26/17 (MBUX multimedia system and instrument cluster (head unit)), and then perform the special procedure for reinitializing the ASSYST data in powertrain control unit N127. |
| LI00.20-P-077615 | 2026-06-02. Service bulletin. ELECTRICAL SYSTEM. Complaint 1. "Perform vehicle handover" in the workshop menu to start the maintenance computer for service A/B cannot be carried out. 2. Service confirmation is not possible because "Perform vehicle handover" is displayed. This cannot be carried out. 3. The service display in the instrument cluster permanently displays 365 days (remaining time) and does not change. Cause Routine change in the software in N133/1 (instrument cluster) or A26/17 (MBUX multimedia system and instrument cluster (head unit)). Vehicle handover was not performed. Remedy For model series 290 AMG up to and including AEJ 22 and model series 167 up to and including AEJ 21/2, the following applies: Manually commission already-installed instrument cluster control unit N133/1 and then perform special procedure to re-initialize ASSYST data in N127 powertrain control unit. For model series 167 as of AEJ 22/1, 192 AMG, 206, 214, 232 AMG, 236, 254, 290 AMG as of AEJ 23, 294, 295, 296, 297 and 465, the following applies: Reinitialize ASSYST Plus under Adaptations – Teach-in processes – ASSYST PLUS in control unit N133/1 (instrument cluster) or A26/17 (MBUX multimedia system and instrument cluster (head unit)), and then perform the special procedure for reinitializing the ASSYST data in powertrain control unit N127. |
| PSL-NCU Return Parts 5/22 | 2026-06-01. Other. POWER TRAIN; STRUCTURE:BODY. Dear Mercedes-Benz USA Dealers, The part numbers listed in the chart below should no longer be installed, and any existing stock must be returned to your facing PDC. The deadline for all dealer returns is no later than Thursday, June 11, 2026. After June 11th, returns of these parts will no longer be accepted. These parts should be returned via ZSR Special Return, using item category SCM Authorized Part Return. Please include a copy of this NCU as your authorization to return these parts. This procedure will not affect your return allowance. All returned parts will be replaced in accordance with the chart provided below. |
| LI82.30-P-059239 | 2026-05-20. Service bulletin. VISIBILITY/WIPER. Complaint There are several types of complaint about noises or poor windshield wiper wiping performance: A: Wiper blades squeaking, chattering, shuddering B: The windshield is not wiped completely (streaking) C: During the downward movement water is pulled back onto the windshield from the A-pillar (Figure 1) D: After windshield cleaning, water keeps spraying onto the windshield for several wipe cycles (Figure 2) A1: The windshield and wiper blades are contaminated with residues from car washing facilities, identifiable by the water beading. The resulting differences in the friction values between the wiper blades and the windshield can excite the wiper blades to vibrate. Note: It is mostly wax residue from the washer system, but also water-repellent nano-particle coating for paint and/or silicone-based washer fluid, that could cause this problem. A partially dry windshield also has different friction values, which can likewise result in squeaking of the wiper blades A2: The wiper blades are worn by mechanical damage (wiper lip damaged by ice or insect debris, or deformed by long periods of disuse). A3: Incorrect angle of incidence of the wiper arms to the windshield. Because of this, the rubber lip of the wiper blade may not flip over at the reversal point. Cause B: B1: Wax/ dirt residues on the windshield B2: Wiper blades deformed or worn B3: Downforce of wiper arm not OK (Figure 3) Cause C: Water is pulled back onto the windshield by the differential pressure created as the wiper arm moves downwards. Cause D: Washer water collects in the fastening of the wiper blade and is blown onto the windshield by the airstream over several wipe cycles. Note and supporting information: Wiper blades are wear parts which, even when "not used" for long periods (kept in park position), may become permanently deformed and damaged. Further stresses on the rubber wiper blade arise due to various environmental influences which progressively change the effectiveness of the rubber wiper blade and accelerate the aging process. Due to the natural aging process and wear, the wiper blades should be replaced twice a year, preferably in Spring and Fall (see operator's manual). Remedy Remedy A: A1: Cleaning entire windshield with A 000 986 40 71. A2: Checking water's flow behavior after windshield has been cleaned (see Video 1). If, after cleaning, there are still areas with water beading, then the cleaning process must be carried out again until a rejection reaction is no longer present. • Note: On the vehicle in the video (Video 1), water still beads on the bottom left of the windshield. The windshield is still not properly clean, even though it appears to be clean. The windshield is only properly clean when there are no more areas on the windshield where water beads. A3: Replace wiper blades with genuine wiper blades. Important: Only exchange wiper blades if windshield no longer has water-repellent areas Note: Replacement of wiper blades is not covered under warranty and can be replaced at the expense of the customer. Remedy B: B1: Clean windshield with intensive cleaner A 000 986 40 71. Important: Do not clean the wiper blades otherwise the graphite coating will be damaged. B2: Replace wiper blades with genuine wiper blades • Note: Replacement of wiper blades is not covered under warranty and can be replaced at the expense of the customer. B3: Check the wiper arm for excessive resistance in the bearing. Restore mobility or replace wiper arm if necessary. Remedy C: Problem inherent in design for which there is no technical remedy. Exception: X204 up to 02/2014. In these vehicles, it is possible to install the design configuration of vehicles as of 02/2014. This includes wiper arms (styled arms) with improved behavior in this respect. It is also necessary to replace the wiper blades because the styled arms feature a Top Lock connection (previously Side Lock). |
| LI07.10-P-080384 | 2026-05-20. Service bulletin. ENGINE. Complaint Customer reports Check Engine Light with possible loss of power concern. The Following DTC's are present • P210185 - The throttle valve actuator has a malfunction. There is a signal above the permissible limit value. • P213500 - The values from the position sensors of the throttle valve are implausible relative to each other • P213600 - The values from position sensors "A/C" of the throttle valve are implausible relative to each other • P210B85 - The throttle valve actuator 2 has a malfunction. There is a signal above the permissible limit value. • P2AD300 - The values from the position sensors "A/G" of the throttle valve are implausible relative to each other Cause Increased electrical resistance in pins for left and right throttle actuators. (M16/60 and M16/61) Remedy Replaced left and right throttle actuator Sockets with updated part. Silver Coated Pins 8x A 003 982 70 26 (according to wiring diagram 0,5mm) Gold Coated Pins 4x A 003 982 75 26 (according to wiring diagram 0,75mm) ELA Seals 12x A 001 545 50 80 |
| LI40.10-P-061032 | 2026-05-18. Service bulletin. SUSPENSION; WHEELS. Complaint Noises at the front axle when cornering or maneuvering (video files attached) Note: Save video files locally and play them with Windows Media Player. Cause Driving with summer tires in combination with low outside temperatures. At low outside temperatures or in wet conditions, a noise may be produced at the outer wheel on the front axle while maneuvering with sharp steering angles. Note: AMG vehicles with 4MATIC of model series 217 (without code 494) and model series 222 have a modified axle geometry compared with series production vehicles to provide more sporty handling. The problem cannot be remedied by changing the axle settings. |
| PSL-NCU Return Parts 5/15 | 2026-05-18. Other. SUSPENSION; POWER TRAIN. The part numbers listed in the chart below should no longer be installed, and any existing stock must be returned to your facing PDC. The deadline for all dealer returns is no later than Thursday, June 4, 2026. After June 4th, returns of these parts will no longer be accepted. These parts should be returned via ZSR Special Return, using item category SCM Authorized Part Return. Please include a copy of this NCU as your authorization to return these parts. This procedure will not affect your return allowance. All returned parts will be replaced in accordance with the chart provided below. |
| LI07.10-P-080384 | 2026-04-29. Service bulletin. ENGINE. Complaint Customer reports Check Engine Light with possible loss of power concern. The Following DTC's are present • P210185 - The throttle valve actuator has a malfunction. There is a signal above the permissible limit value. • P213500 - The values from the position sensors of the throttle valve are implausible relative to each other • P213600 - The values from position sensors "A/C" of the throttle valve are implausible relative to each other Cause Increased electrical resistance in pins for left and right throttle actuators. (M16/60 and M16/61) Remedy Replaced left and right throttle actuator Sockets with updated part. Silver Coated Pins 8x A 003 982 70 26 (according to wiring diagram 0,5mm) 4x A 003 982 75 26 (according to wiring diagram 0,75mm) ELA Seals 12x A 001 545 50 80 |
| LI20.10-P-072886 | 2026-04-27. Service bulletin. ENGINE. Complaint CEL ON with DTC P012800 "The Coolant Temperature is Below the Specified Temperature" active and stored in the ME (N3/10). There are no drivability concerns related to the complaint. Cause Root cause varies Remedy Prior to performing any repairs for this complaint: With a cold engine, pressurize the high temp coolant circuit and while it's under pressure, release the cap on the low temp coolant circuit and check if the pressure drops right away or not. If the pressure drops, the lower hoses are swapped. Correct this, fill, bleed and test drive the vehicle. If the complaint returns, then continue with the steps below. IMPORTANT: Use VMI to check for emission extended warranty – Engine Thermostat (incl. software update) MY19-23, Various Models and Platforms (167, 190, 205, 213, 217, 222, 223, 232, 253, 290, 463) If the vehicle is covered under an emission extended warranty, Please perform steps outlined in the NCU for repairs. If vehicle is not covered under an emission extended warranty, then proceed as follows: Check for available software updates to the ME (N3/10). If updated software is available, perform the update, clear the DTC and the perform each of the "WARM START" and "COLD START" test drives listed below twice. If the code does not re-appear then release the vehicle If there is no new software available OR the DTC returns after the test drives then perform the following steps: • Drain the coolant through a fine mesh sieve and check for signs of debris. Additionally, inspect the coolant reservoir for debris. If any debris is found, flush the system several times to clear as much of the debris as possible • Replace the thermostat and bleed the system as outlined in AR20.00-P-1142-04A, evacuate the system for 20-30 minutes instead of the 5 minutes specified in step 22 • NOTE: Please use all the tools specified in the AR document • NOTE: There are two valid thermostats to choose from in the parts section of this LI. Please verify which PN is applicable for the vehicle being worked on via XENTRY Parts Information • After bleeding the system clear the DTC and perform each of the "WARM START" and "COLD START" test drives listed below twice. If the DTC does not reappear after the tests, release the vehicle If there is no new software available, the thermostat has already been replaced, and the DTC returns open a TIPS case and attach the following documents: • Initial quick test • ME (N3/10) control unit log • The results of an R48 test from a “yes” response and from a “no” response WARM START · Begin with the engine coolant temperature at approximately 50 degrees C · Activate the AC system, if defrost is not in use open the windows · Drive the car normally until a coolant temperature of 75 degrees C is achieved · Depress the accelerator pedal 50% for ~5 seconds (partial acceleration) · Let off the accelerator pedal and let the car coast for ~10 seconds · Continue to drive the car normally COLD START · Drive for ~7 miles (normal driving) · Shut off the engine in a parking lot (or similar), wait 30 seconds, then restart and continue driving · Depress the accelerator pedal 50% for ~5 seconds (partial acceleration) · Let off the accelerator pedal and let the car coast for ~10 seconds · Continue to drive the car normally |
| LI82.10-P-078301 | 2026-04-27. Service bulletin. EXTERIOR 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. 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 |
| LI00.01-P-078887 | 2026-04-25. Service bulletin. UNKNOWN OR OTHER. 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 |
| LI33.20-P-078406 | 2026-04-17. Service bulletin. SUSPENSION. 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. See also: LI35.30-P-058566 (Axle Half Shaft noise when changing direction - Front) LI33.30-P-056665 (Axle Half Shaft noise when changing direction - Rear) LI40.10-P-059248 (Wheel cracking noise when cornering) Remedy 1. Perform Operation A and evaluate by testing vehicle. 2. If noise is still present after re-testing: • If 192/232 chassis, verify FIN is in the listed range below in "Operation B" and perform. • If not 192/232 chassis or vehicle is a 192/232 not in the listed FIN range, additional verifications of where the noise is coming from are needed. Use multiple channel NVH method to narrow down location. Verify the LI's listed above were completed or if there are other similar noises associated with the chassis (Example: 192/232 also has under panel noises and an associated LI). Operation A: 1. Clean contact surfaces of wheel bearing and steering knuckle with brake cleaner (see areas marked blue in pictures "2.jpg" and "3.jpg"). NOTE: The front area of the wheel bearing and the seals must not come into contact with the cleaner, otherwise, the sealing rings will be damaged. 2. Clean threads of wheel bearing mounting. 3. Thinly coat contact surfaces of wheel bearing, steering knuckle, and axle mating face with Molykote (annular joint grease) (see areas marked blue in pictures "2.jpg" and "3.jpg"). NOTE: Axle mating face greasing is also covered in LI35.30-P-058566 and LI33.30-P-056665. Operation B (Only applies to 192 and 232 in listed FIN range): Only affects vehicles up to FIN end number: • Model series 192: xxx xxx xx 002 876 • Model series 232: xxx xxx xx 022 312 1. Replace steering knuckle. 2. Wheel bearings do not need to be replaced. |
| LI27.60-P-080449 | 2026-04-14. Service bulletin. POWER TRAIN. Complaint Harsh upshifts, downshifts, or jolting in lower gears when accelerating. Cause Incorrectly installed (rotated) rotational speed sensors on the EHS (VGS Control Unit) can cause abnormalities in signals. As a result, poor adaptation values are stored and harsh gearshifts are felt. This only affects vehicles with VGS control units produced between days 182-296 of 2025 (July 4, 2025-October 23, 2025). Remedy 1. Collect initial transmission EEPROM file 2. Check EEPROM .txt file for VGS control unit serial number and production date (attachment figure 1) - If the valve body is already removed, you can inspect the control unit for its stamped serial number (attachment figure 2) If the production date is or is within 25182-25296 (07/4/25-10/23/25): The complete valve body will require replacement. 1. Remove transmission oil pan & inspect fluid/pan/filter condition - compare findings to extended fluid condition examples provided in Xentry blue book under general information for VGS 2. Replace complete EHS valve body, fill to near max fluid level, & complete initial start-up - Ensure all oil guide pipes are installed in the new valve body to prevent a new concern after replacement. (See photos in WIS instructions) - Verify the new valve body production date is outside of day 182-296 of 2025 (attachment figure 2) If the production date is outside of this range: This LI is not applicable. 1. Perform IPR and follow recommended instruction |
| LI54.71-P-079104 | 2026-04-10. Service bulletin. ELECTRICAL SYSTEM. Complaint Traffic sign symbol for "Traffic Sign Assist" is blinking in instrument cluster without obvious cause usually with one of the following scenarios: • Flashing without a speed limit ("- -"). • Flashing when current vehicle speed is under speed limit. • Flashing between US speed limit symbol and European speed limit symbol. NOTE: • Verify that the concern falls under one of the attachment videos. If not, then it is outside of the scope of this LI. • This also does not cover "Traffic Sign Inoperative" messages on the instrument cluster. Cause There are two identified reasons for this concern: 1. Country code information stored incorrectly at a particular geographic latitude range. 2. Incorrect reference data when the vehicle is started and a GPS signal is not immediately available. Remedy No TIPS case is necessary. Do not replace parts. A new software for the head unit is scheduled for tentative release in Q2 2026. |
| LI00.01-P-078887 | 2026-03-28. Service bulletin. UNKNOWN OR OTHER. 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 • 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 • P3 Hybrid = AMG Plug-in Hybrid with rear drive unit • 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 |
| LI82.85-P-078722 | 2026-03-17. Service bulletin. ELECTRICAL SYSTEM. Complaint The vehicle's position on the map is displayed far away from its actual position, e.g. the vehicle is displayed as being in the middle of the ocean. Note: No relevant DTC is displayed during the quick test. Cause The GNSS antenna is not correctly inserted at the GNSS connection (see picture in the attachment) in the head unit (A26/17). Remedy Insert the plug into the GNSS connection and ensure that the plug has engaged correctly. |
| LI54.65-P-080132 | 2026-03-17. Service bulletin. ELECTRICAL SYSTEM. Complaint 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active Parking and Parking Assist Inoperative" on Instrument Cluster 5. Cameras 6. Other Park Topics Cause Various root causes Remedy See attached diagnostic guide. |
| NCU - 2025120009 | 2026-03-14. Service campaign. ELECTRICAL SYSTEM; POWER TRAIN. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the drivetrain control unit does not meet current production specifications. The system may experience an excessively high quiescent current draw on the vehicle, which could lead to an increased discharge of the 12V battery. MBUSA will conduct a service campaign. An authorized Mercedes-Benz dealer will update the drivetrain control unit software. |
| LI82.10-P-078301 | 2026-03-11. Service bulletin. EXTERIOR 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. 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 |
| LI54.10-P-073164 | 2026-03-10. Service bulletin. ELECTRICAL SYSTEM. Complaint Yellow information message in driver display (instrument cluster): "Switch on motor to charge the 12V battery" Cause The state of charge (SOC) of the 12V battery has dropped to 45% or less. Remedy This warning message appears as soon as the state of charge (SOC) of the 12V primary battery drops below 45%. This message is displayed to safeguard the vehicle's starting ability. At the same time as the display appears in the instrument cluster, customers with a linked Mercedes me connect account also receive a push notification via the app/by email (if this function is activated). The battery must be charged to a state of charge (SOC) of at least 50%. To do this, an external charger can be connected (please comply with AR54.10-P-1133S) or the vehicle can be driven (by the customer) for 30 to 60 minutes. Please make customers aware of how the vehicle behaves: • If the vehicle is used for short journeys, the battery state of charge may slowly drop to less than 45% – a negative charge balance • A negative charge balance will also occur if the vehicle is used while stationary without running the engine, e.g. if the head unit is used, the ignition is switched on, or other comfort & convenience power consumers, e.g. seat heating/seat ventilation, are active. • An unlocked vehicle may increase consumption, because certain vehicle functions are actively kept ready for the customer. In combination with Keyless-Go or flush-mounted door handles, the vehicle may be woken up if the vehicle key is detected in the vicinity of the vehicle. The cause of the discharge can be identified with the aid of the onboard electrical system data in the EZS using XENTRY Diagnosis. See attached examples for identifying typical customer situations (e.g. operation with ignition on, operation of head unit while stationary or vehicle unlocked while parked). Vehicles with code B01+801: When charging while stationary, the 48V battery must have a state of charge (SOC) of 70% before the 12V primary battery, or the secondary battery in the case of code 503, can be charged. To ensure optimum battery care, please also comply with the existing Service Information documents regarding the handling of stock vehicles (SI54.10-P-0024A) and on remaining in transport mode (SI54.00-P-0004A) until immediately before handover to end customers. Special note: Do not replace any parts, if the message has occurred due to battery discharge as a result of the driving profile or the ignition being switched on (see attached examples); in such cases separate warranty and goodwill invoicing is not possible, as this is a normal on-board electrical system protection function. Likewise battery care and recharging do not qualify as a W&G case. Please advise customers accordingly regarding the above-mentioned issues relating to vehicle use. |
| LI54.21-P-080326 | 2026-03-10. Service bulletin. ENGINE. Complaint CEL light on with no drivability concerns. Cause Signal timing error. Remedy This fault code does not cause a drivability concern and will clear itself within 2-3 key cycles. The vehicle can be released back to the customer. There is software in development for this concern. |
| LI54.10-P-069698 | 2026-02-28. Service bulletin. ELECTRICAL 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 identifying the correct Remedy. 1. No start 2. Yellow or red instrument cluster message for 48 V on-board electrical system battery (G1/3) 3. Limp home mode, overheating, A/C not blowing cold, or loss of acceleration 4. Check Engine Light Cause Cause 1: Software causes Intermittent No Starts with fault B183387 in DC/DC converter N83/1 Cause 2: Software causes Permanent No Start with fault B183349. May also have fault B183371. Cause 3: Hardware short circuit in 48V system causes fault B183319 in 48V battery. May also have fault B183371. Cause 4: Internal 48V battery Peltier cooling element failure causes fault B183397 Cause 5: This will Always have fault code B183371 but different from cause 2 and 3 -- it will Not have B183349, B183319, or any other faults in the 48V battery. This will only have fault B183371 in 48V battery. Cause 5 is from the 48V battery detecting an abnormality which then causes the 48V battery to disconnect itself. The disconnected 48V battery then causes subsequent symptoms: Limp Home Mode, overheating, A/C not blowing cold, or loss of acceleration Cause 6: Check Engine Light with fault P0606F1 in the N127 PTCU Cause 7: Check Engine Light with possible no start and fault P057FF1 Remedy Note: each of these remedies correspond to a specific cause. Make sure to match correct Cause with Remedy. Remedy 1: 1. Check the 12V power supply and LIN connection 2. Update software in G1/3 (48V battery) using newest XENTRY software and Add-ons 3. Road test and release vehicle if no further symptoms Remedy 2: 1. Charge the 12V battery (Charging current <5A) 2. Update software in G1/3 (48V battery) using newest XENTRY software and Add-ons 3. Road test and release vehicle if no further symptoms If the faults return or cannot be cleared: 1. XENTRY MUST be connected with VCI cable to correctly complete this remedy. 2. Complete guided test for B183349. 3. If guided test completes, vehicle starts, and drive cycles show no further symptoms, release vehicle. 4. If after guided test completes, XENTRY states to replace 48V battery: replace only 48V battery. If vehicle is a MY21 w/M256 engine, update SW in 48V battery 5. If this is a repeat visit for fault B183349 and guided test has already been completed, open a TIPS case. 6. If guided test does not complete OR symptoms are still present open a TIPS case. 7. If communication cannot be established with 48V battery perform physical layer check at 12V wiring to DCDC. If no abnormalities found, replace the 48V battery. 8. If guided test completes but a new fault code is present (such as B183319, B183371, etc.) follow the relevant Cause/Remedy for that fault in this LI. Remedy for 3: (If this occurred after Campaign 2025050001, this Li does not apply and LI54.10-P-079772 should be followed) 1. If fault is not Current (only Stored): 1. Update software in G1/3 (48V battery) using newest XENTRY software and Add-ons 2. Road test and release vehicle if no further symptoms If the faults return or this is a second visit after the SW update: 1. Complete the guided test for B183319 2. Perform XENTRY actuations for all 48V components. 3. Create a TIPS case with ALL Preliminary measures required as noted below for Remedy 5 4. Upload to TIPS case ISA performance data from the N129. 5. ISA performance data location in XD: 6. N129 control unit under Special Procedures 7. "Procedures for support queries to market support" 8. "Collation of diagnosis performance data" 9. "engine at idle" See attachment for further instructions. |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.