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Service bulletins for the 2019 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.

242 on file from NHTSA, as of 2026-10-19.

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Only bulletins with component: Electrical system are shown. Show all

Bulletins, newest first
LI54.21-P-0803262026-10-02. Service bulletin. ELECTRICAL SYSTEM. Complaint CEL light on with no drivability concerns. Cause Signal timing error. Remedy 167, 465: SW has been released. Update the FSAM to the latest SW version. 290, 118, 243, 247: 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.
LI54.65-P-0801322026-08-12. 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.
LI54.21-P-0803262026-07-24. Service bulletin. ELECTRICAL SYSTEM. Complaint CEL light on with no drivability concerns. Cause Signal timing error. Remedy 167, 465: SW has been released. Update the FSAM to the latest SW version. 290, 118, 243, 247: 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-0776152026-07-06. 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. The following applies to model series 167 from AEJ 22/1 onward, 192 AMG, 206, 214, 223, 232 AMG, 236, 254, 290 AMG from AEJ 23 onward, 294, 295, 296, 297 and 465: 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.
LI54.21-P-0803262026-07-06. Service bulletin. ELECTRICAL SYSTEM; 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, 118, 243, 247: 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-0807032026-06-16. 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-0776152026-06-16. 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.
LI82.85-P-0805072026-06-02. Service bulletin. ELECTRICAL SYSTEM. Complaint After successful commissioning of the HERMES control unit (N112/9) with XENTRY Diagnosis DVD 03/2026, the message "SOS - service not activated" appears on the instrument cluster. In addition, the following two conditions are also met: • HERMES (N112/9) control unit: event code B15CE00 is ACTIVE and STORED (A+S) • Vehicle Documentation System: For the HERMES control unit, the EID1, EID2, ICCID, IMEI, IMSI, TELNR fields in the "Identification/Serial number" column have the value "-" Cause Still under analysis Remedy Recommission the HERMES control unit (N112/9) with XENTRY Diagnosis 03/2026 and add-on 33399 installed or carry out the procedure with a newer version of XENTRY Diagnosis: XENTRY→ "N112/9 - Control unit for telematics services (HERMES)" -> "Adaptations" -> "Control unit commissioning" -> "Commissioning of previously installed control unit"
LI82.85-P-0805592026-05-29. Service bulletin. ELECTRICAL SYSTEM. Complaint The customer requests deactivation of the N112/9 HERMES communication module Note: Deactivation of the HERMES control unit (N112/9) is not supported for gray-market vehicles. Cause Before deactivating the HERMES control unit (N112/9), it must be clarified by the legal department of the respective MPC whether and under what conditions deactivation may be carried out. If deactivation is not permissible under applicable law, the HERMES control unit (N112/9) must not be deactivated. Remedy Please inform the customer that, following deactivation, the vehicle will no longer be able to place an automatic emergency call, nor will the customer be able to place a manual emergency call. After deactivation, the Mercedes-Benz Digital Extras will also no longer be available. Please have the attached sample form checked by your market's legal department, adapted to local requirements if necessary, and approved. Furthermore, after informing the customer about the effects of deactivation, please have the workshop complete and sign the approved form together with the customer, and send it to the MPC via a TIPS case for audit-compliant documentation. Furthermore, the workshop must affix a sticker to the emergency call button cover on the overhead control panel and to the emergency call button itself. After affixing, pictures of the overhead control panel need to be attached to the TIPS case for audit-proof documentation. After deactivation, the HERMES control unit (N112/9) is in the "Out of Service" operating status, and the display "SOS NOT READY" appears in the Audio/COMAND system. This display message tells the customer that the emergency call function is not available. In detail, the following steps must be carried out 1. The workshop must inform the customer about the effects of deactivation (see above) 2. Legal review by the MPC Legal department to determine whether deactivation is permissible for the vehicle and provision of a market-specific customer form based on the examples (see "Example - Deactivation communication module HERMES customer declaration English V3.0.pdf") 3. Completion of the market-specific customer form by the workshop and obtaining the customer’s signature 4. Creation of a XSS ticket by the workshop for the MPC with the signed customer form attached 5. Written confirmation of legally reviewed and approved deactivation by the MPC in the TIPS case (see attachment How+to+request+adding+Code+09o+via+XSS+v2.pdf, point 1) 6. Creation of an XSS ticket for documentation of the SA code "09o" (zero nine oh) in the Vehicle Documentation System (see attachment How+to+request+adding+Code+09o+via+XSS+v2.pdf, steps 2–7) 7. Ordering of stickers (part number A9078172900), quantity: 2 8. Affixing of the sticker (part number A9078172900) to the cover of the emergency call button on the overhead control panel (see attachment HERMES-Deactivation_+pictures+of+sticker.png) 9. Affixing of the sticker (part number A9078172900) to the emergency call button on the overhead control panel (see attachment HERMES-Deactivation_+pictures+of+sticker.png) 10. Taking photos of the applied stickers and attaching them to the TIPS case 11. After the XSS ticket has been successfully processed, the communication module must be deactivated using XENTRY: • Connect XENTRY Diagnosis • Access the HERMES control unit (N112/9) • "Adaptation" tab, menu item "Teach-in processes" -> "Deactivation" • Follow the instructions
LI54.65-P-0801322026-05-14. Service bulletin. BACK OVER PREVENTION: WARNINGS; ELECTRICAL SYSTEM; LANE DEPARTURE: BLIND SPOT DETECTION. 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.
Emissions - 20260200062026-04-25. Emissions. ELECTRICAL SYSTEM; ENGINE. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles equipped with an 8-cylinder engine, the software of the engine control unit may not correspond to the current specifications. Under specific conditions, the OBD system may not detect an aged catalyst, which could impair the engine’s ability to adjust the catalyst heating, potentially resulting in increased exhaust emissions. MBUSA will conduct an emission service campaign. An authorized Mercedes-Benz dealer will update the engine control unit software on the affected vehicles.
LI82.85-P-0787222026-03-17. 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-0801322026-03-17. 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.
LI54.10-P-0731642026-03-10. 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.
LI54.65-P-0801322026-02-28. 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.
LI54.10-P-0696982026-02-28. 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.
NCU - 20241000162026-02-27. Emissions. ENGINE; ELECTRICAL SYSTEM. Mercedes-Benz AG (“MBAG”), the manufacturer of Mercedes-Benz, has determined that on certain MY 2019-2021 G-Class, S-Class and GT (463, 222 & 190 platforms) vehicles, the engine control unit software does not correspond to current production specifications. It is therefore possible that onboard diagnostics and/or exhaust gas emissions requirements may not be fulfilled. MBUSA will conduct a service campaign. An authorized Mercedes-Benz dealer will perform the ECU software update.
LI27.19-P-0802192026-02-17. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. Complaint Check engine light on with the following fault is current in the VGS Control Unit: P084300 Oil pressure sensor 'A' has a short circuit to positive stored in VGS control unit. Cause Electrical failure of oil pressure sensor integrated into VGS Control Unit Remedy Intelligent Predictive Repair (IPR) recognizes this fault pattern and will provide the necessary repair suggestion. 1. Perform IPR and follow the recommended procedures 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.
LI54.65-P-0801322026-02-14. 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 - 20240900072026-02-13. Service campaign. ELECTRICAL SYSTEM; ENGINE. 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 engine control unit software.
LI54.71-P-0802362026-02-06. Service bulletin. ELECTRICAL SYSTEM. Complaint Red ring displayed around vehicle when front or rear camera door actuates. Please also see LI54.65-P-080132 for additional listed red ring causes. Cause EMF interference. Remedy Camera functionality is not affected. Cameras and displays operate normally. For vehicles with a front facing actuating camera and flap (223 and 297): • 223, 297 > Install clip on ferrite magnet on M35/1, pin 3. For vehicles with rear facing camera (223, 213 Facelift, 238, 257, 290, 297): • 297 > Install 2 x ferrite magnets on M35/2, pin 3 and 4. • 213 Facelift, 223, 238, 257, 290 > Install on M35/2, pin 4
LI54.65-P-0801322026-01-31. Service bulletin. ELECTRICAL SYSTEM; BACK OVER PREVENTION: WARNINGS. 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.
LI82.85-P-0787222026-01-27. 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-0801322025-12-15. 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.
LI54.30-P-0800902025-12-09. Service bulletin. ELECTRICAL SYSTEM. Complaint The Head-up display (HUD) may be perceived as too bright and without adjustment. Cause Signal from the rain/light sensor is not recognized/processed correctly. As a result, the HUD is permanently displayed at maximum brightness. The customer has the option to turn off the HUD via MBUX. Remedy Software update of the "Head-up display" control unit.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.