Sorry to say that it . . . .
sounds like the blower regulator is gone again.
Not sure of the numbers but it blower should go from hi to low speed as you spin the dial (Min - Auto - Max).
Maybe good news it's still under warranty. Also make sure that the 'white' grease make good contact with the blower's housing to dissipate the heat in the regulator.
Regards . . . . JimF
'94 S500 Cpe
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