Blower motor will not work at all. on 1997 Mercedes-Benz S320

Blower motor will not work. Tested wires red is hot blue is hot and motor housing is hot. pulled motor tested red wire it is hot tested blue it is not hot . put 12v battery on motor it works. Something is making motor and housing test hot when installed tests ok when pulled out.
Thank you for any help Is regulator and resistor same?
motor should work on hi if they are bad right?

Asked by for the 1997 Mercedes-Benz S320
first: regulator and resistor, not the same thing. second: if motor bad it will never work. the problem should be the regulator. the wire cluster that plugs into fan.