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Service bulletin LI20.10-P-076206

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id11024266
Published by NHTSA2025-10-14
Manufacturer's numberLI20.10-P-076206
Manufacturer's date2025-10-13
NHTSA componentENGINE

NHTSA's summary

Complaint Customer states that the CEL is lit in the instrument cluster. Various codes may be active/stored: Stored in N3/10 in model series 206, 254 or 232: P012800 - The coolant temperature is below the coolant thermostat specified temperature. and/or P01169D - Malfunction in coolant temperature sensor 1. Under temperature in the component or system. For model series 177, 118, 247 in n3/10 (only valid for M139.980 facelift (code 9U8)): P2CEF00 - Electrical fault or open circuit in coolant thermostat. and/or P011685 - Malfunction in coolant temperature sensor 1. There is a signal above the permissible limit. Cause Debris in the coolant system Remedy An updated thermostat must be installed. Order the correct thermostat part number for your application: CLA45/GLA45 with SA Code 9U8: A 139 200 66 02 CLA45/GLA45 WITHOUT SA Code 9U8: A 139 200 27 02 All other M139 equipped vehicles: A 139 200 64 02 New screws must also be ordered and used when installing thermostat A 139 200 66 02 or A 139 200 64 02 PN N000000006341 (qty 2) will be used in place of the existing M8 screws. on the face of the thermostat. The new screws must be torqued to 8 Nm. Follow the instructions in WIS for removal and installation with the exception of the thermostat screw torque value mentioned previously. After replacement, fill and bleed the coolant system per the instructions in WIS for the model that is being worked on. QC the car on a test drive. If the complaint is remedied, release the vehicle.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Engine

Trouble codes named

P0116, P0128, P2CEF

Vehicles listed
MERCEDES-BENZ AMG C432023 to 2024
MERCEDES-BENZ AMG C43 4MATIC2023
MERCEDES-BENZ AMG CLA452020 to 2024
MERCEDES-BENZ AMG GLA452021 to 2023

Listing a model year does not mean every vehicle of it is concerned: the document says which.