Volvo Repair: 1998 V70 AWD 2.5 Turbo, position sensors, agravation

Question
When I change the selector, the fan blows air to different areas.  It seems lke it is less but maybe that is because of the lack of heat, which I believe is the #1 problem.  So based on your comments, that would be the position sensors, motors or computer.  Any way to check that?  A Volvo parts manager said there is an adjustment that can be made.  Is this true?  Can that be done manually?   

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Followup To
Question -
I have a 1998 V70 AWD 2.5 Turbo.  I am having trouble with heat in the passenger compartment.  Very little air is being blown into the car and it is quite cool.
Answer -
The amount of air blowing into the car is dependent on the fan.  The temperature is determined by a blend door that routes a certain amount of air through the heater core.  Is the fan working or is it just coming out another vent like the floor or defroster?  The doors are controlled by the climate computer, they're DC motors that have position sensors in them so a position sensor may be out, or a motor may be bad.  The control module may be bad too, not controlling the motors for any of the doors anymore.

James

Answer
The door end positions can be reset to recalibrate the position sensors but this is something that can only be done with a volvo scan tool.  You don't have to go to a dealer for this but you won't find it at any independent unless they specialize in volvos.  Its hard to know whats going on back there unless you pull the dash out to do electrical troubleshooting.  The only other way to know is to use the volvo scan tool to monitor the climate module operations to determine where the failure is.  Probably best to take it to a specialist.  Will save you alot of agravation but you can maybe still do it yourself.

James