My blower motor on my 96 seville sometimes stays on for a few minutes after I turn the key off and the climate control goes crazy, I can't turn it off, its got a mind of its own. I have replaced the climate Control panel but it still does the same thing. Sometimes it works perfect for a few days the all of a sudden it goes crazy.
CHART 3 - BLOWER ON CONTINUOUSLY
Airflow is controlled by modulating commanded blower motor voltage. Blower speed is a function of the program number when it is under automatic control, with adjustments made by vehicle speed, coolant temperature, and solar load. Special cases may override normal operation.
If blower is inoperative in normal operation, but operates properly in override, the IPC or data line between IPC and APC may be faulty.