480A90 is a fault stored in your BMW's memory (an ISTA fault code, not a standard OBD-II P-code).
What it means: DSC: roller brake tester mode active. The car believes it is on a dyno / roller brake tester (inspection), so it temporarily disables part of the stability functions. Usually NOT a fault — a leftover from diagnostics. Switch the car off, wait 5 minutes, restart; if it stays, clear the code with a scanner.
