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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 id11020640
Published by NHTSA2025-07-10
Manufacturer's numberLI20.10-P-076206
Manufacturer's date2025-07-08
NHTSA componentENGINE

NHTSA's summary

Complaint Customer states that the CEL is lit in the instrument cluster Cause Debris in the coolant system Remedy An updated thermostat must be installed. Order the correct thermostat part number for your application: CLA45/GLA45: A 139200 66 02 All other M139 equipped vehicles: A 139 200 64 02. New screws must also be ordered and installed with the revised thermostat, 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

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

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