Audi S4 2004–2005 — technical service bulletin
Bulletin 0501 · NHTSA communication 10019414 · issued Feb 2, 2005
Technical service bulletin
communication type
Engine and Engine Cooling
component
2004–2005
model years
2
vehicle entries
Official summary
After-run coolant pump -v51- may not operate when the ignition is shut off and the coolant temperature is above 112 degrees c. *tt
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.