Heat Door Actuator

I was recently told by a mechanic that my 'heat door actuator' is bad. Does anyone know what this is and if the part is available?

Thanks

For what?

it controls something in the heating and ac. it makes a steady clicking sound wen i try to change the position of airflow in my truck.

For what was for the year, but he is right. Dealer part.

oh sorry, 02 sle. do you kno how much this part goes for? could it be replaced by the average joe?

thanx

Part is about 90.00, about 1.5 labor with new procedure that allows this to be done in a simpler access, no way I can say if you can do it, take a look at where it is and see if you feel it is your range of ability.