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Service bulletin LI20.00-P-076708

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 id11023049
Published by NHTSA2025-09-09
Manufacturer's numberLI20.00-P-076708
Manufacturer's date2025-09-09
NHTSA componentENGINE

NHTSA's summary

Complaint Check engine lamp activated, coolant warning message, and engine fan running at full speed. Below fault codes stored in N127 PTCU related to LIN network components. U063200, U063287, U02A900, U02A987, U0698E4, U0698E5, U02C800, U02C887, U063B00, U063B87 Cause PTCU software, or physical layer fault in LIN bus circuit Remedy Model 254 (with version 22A) -Update software of PTCU N127 -Cleared fault codes and check vehicle operation Model 254 after update or with PTCU version later than 22A, or Model 167 -Check connections at all LIN bus components connected to N127 PTCU for damage, corrosion, or poor connection -Check wiring between LIN bus components and N127 for damage or chaffing -Inspect intermediate connections between LIN bus components and N127 for damage, corrosion, or poor connection No software change planned for model 167.

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

U02A9, U02C8, U0632, U063B, U0698

Vehicles listed
MERCEDES-BENZ AMG GLC432024
MERCEDES-BENZ AMG GLC43 4MATIC COUPE2024 to 2025
MERCEDES-BENZ AMG GLC63 S E2024 to 2025
MERCEDES-BENZ AMG GLC63 S E 4MATIC+ COUPE2025
MERCEDES-BENZ GLC 3002023 to 2026
MERCEDES-BENZ GLC 300 4MATIC2023 to 2026
MERCEDES-BENZ GLC 300 4MATIC COUPE2024 to 2026
MERCEDES-BENZ GLC 300 COUPE2024
MERCEDES-BENZ GLC 350 E 4MATIC2025
MERCEDES-BENZ GLE 350 4MATIC2024 to 2025

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