Mercedes-Benz AMG GLC63 2019–2021 — technical service bulletin
Bulletin LI83.20-P-072178 · NHTSA communication 10187784 · issued Jan 4, 2021
Technical service bulletin
communication type
Electrical System
component
2019–2021
model years
11
vehicle entries
Official summary
The customer complains that when the ignition is switched on, pulsating buzzing noises which fluctuate in volume can be heard coming from the area of the instrument panel or the driver's footwell.
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.