Cadillac Repair: cadillac deville 1992, aluminum heat sink, cadillac deville

Question
The heat for this vehicle does not work and the fan blows nonstop

Answer
what have you repaired or had repaired on the vehicle lately ?.

If the blower motor continues to run after you turn OFF the ignition replace the  POWER MODULE which is just above the blower motor and slightly to the left. It has 2 or 3 screws holding it in the top of the large plastic black box and has several wires attached to it. Once removed you will see an aluminum heat sink with fins on it. this is to cool the module.

Replace the POWER MODULE