Dodge Repair: bcm recalibrateing, climate control unit, rear defroster

Question
I let my battery go dead 2010 so i put in a  new one in my 2000 dodge intrepid 2.7lvin R 69475 miles.after my bcm will not reset.Ihave taken out the I O D fuse for 2 hrs.turn the key on can hear the blend doors moveing but the only thing i get is hot air out the defrost vents rear defroster will not come on.The a/c if i hold the button in will try to work is there a way to get the bcm to recalibrate its self? or will need a new one

Answer
The BCM does does play a part in the function of the HVAC system but I would not condemn it without testing a few things first. Because the battery was disconnected, for what I assume was an extended period of time, it is possible that the calibrations for the HVAC actuators have been lost. The quickest way to recalibrate and check for any faults in the system would be to perform the following procedure;

The engine must be running with vehicle not moving.
The Fan Speed set to any speed except OFF.
The Temperature Knob in full cold (full counterclockwise position)
The mode knob must be placed in defrost position (full clockwise position)
The A/C button can be ON or OFF.
Press and hold the Rear Defroster button until the Mechanical Instrument Cluster Odometer display indicates an "AC00". The body control module (BCM) will chime once and the Manual A/C control A/C button LED will begin blinking.
Release the Rear Defroster button and wait until the Manual A/C Control A/C button LED stops blinking. This means that the error check and climate control unit door calibration is complete.

Watch the odometer, if it returns to normal display the BCM has found no faults in the system if it displays a code such as "AC01" or any other two digit number after AC there is something wrong. Perform the above test and re-post if the system is still not right.