Technical Service Bulletin LI27.35-P-080160 — 2020 MERCEDES-BENZ AMG GLC63 S

Complaint (Original LI document #: LI27.35-P-079039) Clicking noises from the electro-hydraulic control unit (EHS) when the vehicle is stationary and ECO Start/Stop is active (combustion engine is off). The noise is more noticeable outside the vehicle and in acoustically shielded areas such as closed rooms or garages. Cause The noise in the valve body (EHS) is caused by superimposed pressure peaks acting on the valves. This phenomenon occurs only after a certain running-in period due to the influence of micro-contamination in the valve bores. Remedy A hardware modification of the electro-hydraulic control unit (EHS) is currently being implemented (no change to the part number). This will be incorporated into series production and as a spare part starting from 12/2025. This is only a comfort-related complaint and has no impact on the functionality or service life of the transmission. For sensitive customers, the following measures can be performed: 1. Replace the electro-hydraulic control unit (EHS), the oil pan, and the transmission fluid. - Ensure all oil guide pipes are installed in the new valve body to prevent a new concern after replacement. (See attached location guide)