Technical Service Bulletins (TSBs) for the 2020 SL550 are official communications between Mercedes-Benz & their dealerships that describe processes for troubleshooting or fixing certain common problems. All vehicle manufacturers are required by U.S. law to make their TSBs available to the public.

    STEERING

    • TSB #LI46.10-P-077314

      Date Announced:
      JAN 24, 2024
      NHTSA ID:
      #10249495

      Noises in the steering column area when steering. Under analysis. Check which area of the steering column the noises occur in. Read More »

    • TSB #LI46.10-P-077313

      Date Announced:
      JAN 24, 2024
      NHTSA ID:
      #10249482

      The steering wheel generates grinding noises between the steering wheel and steering column switch module during steering maneuvers See example file in the attachments area: Lenkrad-Schleifger??A?usch_SteeringWheel-GrindingNoises. Read More »

    • TSB #LI46.15-P-063353

      Date Announced:
      DEC 01, 2022
      NHTSA ID:
      #10228807

      Complaint 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. Read More »

    • TSB #LI46.15-P-063353

      Date Announced:
      SEP 12, 2022
      NHTSA ID:
      #10222461

      Complaint 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. Read More »

    ENGINE (PWS)

    • TSB #LI54.30-P-070482

      Date Announced:
      MAY 19, 2020
      NHTSA ID:
      #10176663

      Check engine indicator light active and fault code P261029/P02FF85/P02FF02 stored in engine control unit Read More »

    ENGINE AND ENGINE COOLING

    • TSB #ELW - M278 Cat

      Date Announced:
      JUL 27, 2023
      NHTSA ID:
      #10240203

      This NCU replaces the prior NCU issued on May 11, 2023, and clarifies replacement part information. In our continuing efforts to assure the proper performance of Mercedes-Benz products and to enhance the satisfaction of our customers, ... Read More »

    • TSB #ELW-M278Catalyst

      Date Announced:
      MAY 11, 2023
      NHTSA ID:
      #10237240

      This extended warranty applies to the following condition that may necessitate the repair or replacement of the catalytic converter system and is related to: a?? A check engine Malfunction Indicator Lamp (a??MILa??) may illuminate due to ... Read More »

    • TSB #LI09.00-P-074093

      Date Announced:
      DEC 08, 2021
      NHTSA ID:
      #10206077

      "MY15+ M278 and M157 Equipped Vehicles with Fault Code ""P023400 a?? Boost Pressure is Too High"" " Read More »

    ENGINE AND ENGINE COOLING:ENGINE:HARD PARTS INTERNAL/MECHANICAL

    ENGINE AND ENGINE COOLING:ENGINE:OIL/LUBRICATION:SEALS/GASKETS

    • TSB #LI1830P0597123

      Date Announced:
      AUG 05, 2016
      NHTSA ID:
      #10205154

      Gasket may settle causing a slight oil leak. Read More »

    ENGINE AND ENGINE COOLING:COOLING SYSTEM:RADIATOR ASSEMBLY

    ENGINE AND ENGINE COOLING:EXHAUST SYSTEM

    • TSB #ELW - M278 Cat

      Date Announced:
      JUL 27, 2023
      NHTSA ID:
      #10240203

      This NCU replaces the prior NCU issued on May 11, 2023, and clarifies replacement part information. In our continuing efforts to assure the proper performance of Mercedes-Benz products and to enhance the satisfaction of our customers, ... Read More »

    ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CATALYTIC CONVERTOR

    • TSB #ELW-M278Catalyst

      Date Announced:
      MAY 11, 2023
      NHTSA ID:
      #10237240

      This extended warranty applies to the following condition that may necessitate the repair or replacement of the catalytic converter system and is related to: a?? A check engine Malfunction Indicator Lamp (a??MILa??) may illuminate due to ... Read More »

    POWER TRAIN:AUTOMATIC TRANSMISSION

    POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE

    • TSB #NCU-2020060009

      Date Announced:
      JUN 19, 2020
      NHTSA ID:
      #10177543

      The software for the transmission control unit on the above model series vehicles transferred to you does not correspond to the current series production configuration. Read More »

    ELECTRICAL SYSTEM

    • TSB #NCU-OTAcommNoMMC

      Date Announced:
      JAN 18, 2024
      NHTSA ID:
      #10249726

      Mercedes-Benz AG (??A?A?MBAG??A?A?), the manufacturer of Mercedes-Benz, has determined that in certain MY 2017-2021 C-Class, CLA, CLS, E-Class, GLC, GLE, GLS, AMG GT, S-Class, SL, and SLC (205, 117, 257, 213/238, 253, 166/292, ... Read More »

    • TSB #LI82.85-P-076800

      Date Announced:
      OCT 10, 2023
      NHTSA ID:
      #10244837

      The "SOS nonfunctional" message appears sporadically in the instrument cluster of the vehicle. The fault code B129C00 is stored in the control unit log. Read More »

    • TSB #NCU-HU SW Update

      Date Announced:
      AUG 28, 2023
      NHTSA ID:
      #10241527

      Mercedes-Benz AG (a??MBAGa??), the manufacturer of Mercedes-Benz vehicles, has determined that on certain MY 2018-2023 C-Class, EQE, EQE SUV, EQS, EQS SUV, GLC, GLE and S-Class (206, 295, 294, 297, 296, 254, 167 and 223 platform) ... Read More »

    • TSB #LI82.85-P-076799

      Date Announced:
      AUG 18, 2023
      NHTSA ID:
      #10241790

      The Mercedes me connect services cannot be activated. The remote status data does not update. Error in N112/9 - control unit for telematics services (HERMES). Read More »

    • TSB #LI72.20-P-075746

      Date Announced:
      JAN 05, 2023
      NHTSA ID:
      #10231032

      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. Read More »

    • TSB #LI68.05-P-060306

      Date Announced:
      JAN 27, 2022
      NHTSA ID:
      #10207198

      Complaint The garage door hand transmitter cannot be initialized with the integrated garage door opener in the inside rearview mirror. Cause 1. Read More »

    • TSB #LI8285P055695

      Date Announced:
      AUG 05, 2013
      NHTSA ID:
      #10205237

      The COMAND unit does not start or the display remains dark. Read More »

    ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL

    • TSB #LI82.85-P-076800

      Date Announced:
      OCT 10, 2023
      NHTSA ID:
      #10244837

      The "SOS nonfunctional" message appears sporadically in the instrument cluster of the vehicle. The fault code B129C00 is stored in the control unit log. Read More »

    ELECTRICAL SYSTEM:SOFTWARE

    • TSB #NCU-HU SW Update

      Date Announced:
      AUG 28, 2023
      NHTSA ID:
      #10241527

      Mercedes-Benz AG (a??MBAGa??), the manufacturer of Mercedes-Benz vehicles, has determined that on certain MY 2018-2023 C-Class, EQE, EQE SUV, EQS, EQS SUV, GLC, GLE and S-Class (206, 295, 294, 297, 296, 254, 167 and 223 platform) ... Read More »

    • TSB #LI8270P056963

      Date Announced:
      AUG 21, 2013
      NHTSA ID:
      #10205234

      Software update of COMAND Online control unit. Read More »

    VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM:ENGINE COOLANT HOSES AND FITTINGS

    LATCHES/LOCKS/LINKAGES

    • TSB #LI72.20-P-075746

      Date Announced:
      JAN 05, 2023
      NHTSA ID:
      #10231032

      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. Read More »

    TIRES

    SEATS

    • TSB #LI91.18-P-077075

      Date Announced:
      DEC 04, 2023
      NHTSA ID:
      #10248162

      Crease formation on genuine leather seat covers in vehicles with low mileage ??A?A? Objects left on the seats for extended periods of time (pressure marks). ??A?A? Objects wedged between the seat backrest and seat cushion (e.g. Read More »

    COMMUNICATION

    • TSB #LI82.85-P-071453

      Date Announced:
      JUL 31, 2020
      NHTSA ID:
      #10179966

      Incorrect time and/or instrument cluster message "SOS, service not activated" and/or Mercedes Me connect services nonfunctional Read More »

    EQUIPMENT

    • TSB #LI82.85-P-076799

      Date Announced:
      AUG 18, 2023
      NHTSA ID:
      #10241790

      The Mercedes me connect services cannot be activated. The remote status data does not update. Error in N112/9 - control unit for telematics services (HERMES). Read More »

    • TSB #LI20.20-P-073274

      Date Announced:
      JUL 08, 2021
      NHTSA ID:
      #10199660

      Coolant warning in instrument cluster - Leak in coolant line Read More »

    • TSB #LI82.85-P-068846

      Date Announced:
      JUL 06, 2021
      NHTSA ID:
      #10199654

      "Free browsing, Internet access via Wi-Fi hotspot and Internet radio nonfunctional" Read More »

    • TSB #NCU-2020060009

      Date Announced:
      JUN 19, 2020
      NHTSA ID:
      #10177543

      The software for the transmission control unit on the above model series vehicles transferred to you does not correspond to the current series production configuration. Read More »

    • TSB #LI72.20-P-070556

      Date Announced:
      NOV 14, 2019
      NHTSA ID:
      #10169586

      EASY-Pack liftgate does not fully open Read More »

    EQUIPMENT:ELECTRICAL

    • TSB #LI82.70-P-071024

      Date Announced:
      JUN 25, 2020
      NHTSA ID:
      #10177565

      The mobile phone address book is not transferred completely to the multimedia system (COMAND or MBUX). In some cases, the call list shows just the telephone numbers but no names. Read More »

    EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.

    • TSB #LI82.85-P-068846

      Date Announced:
      JUL 06, 2021
      NHTSA ID:
      #10199654

      "Free browsing, Internet access via Wi-Fi hotspot and Internet radio nonfunctional" Read More »

    EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM)

    • TSB #LI82.85-P-071453

      Date Announced:
      JUL 31, 2020
      NHTSA ID:
      #10179966

      Incorrect time and/or instrument cluster message "SOS, service not activated" and/or Mercedes Me connect services nonfunctional Read More »

    EQUIPMENT:OTHER:LABELS

    EQUIPMENT ADAPTIVE/MOBILITY

    • TSB #LI82.85-P-068846

      Date Announced:
      JUL 06, 2021
      NHTSA ID:
      #10199654

      "Free browsing, Internet access via Wi-Fi hotspot and Internet radio nonfunctional" Read More »

    UNKNOWN OR OTHER