The blower control module is defective.
A 1998 Cadillac Deville does not have a blower relay. The system has a fuse and a controller to feed power to the blower motor.
The blower motor relay on a 1980 Cadillac Coupe Deville is situated on the passenger side. It is located in the vicinity of the firewall and is just below the windshield.
bad blower motor
Probably the blower motor, wiring to it or control switch
On the fire wall. Behind the engine.
With that year deville...its more than likely the blower motor
blower relay 1992 Caddy sedan deville
AnswerDepends whats broken ie. blows cold, no blower at all ???????no blower at all
when i changed the bm everything worked fine.$60 for the part.
Defective Blower Motor Resistor Pack.
the blower motor is located on the passenger side of the interior under the glovebox.
I have the same problem with a 1991 DeVille that I acquired three days ago. The blower worked fine at first, then would not shut off but would vary speed from the dash control. Now it only runs at high speed in the off position. After shutting off the car, the dampers repositions to the heating position from the cooling position. the blower motor has a high amp draw shorting the control module, replace them both!!!!