The actuator motor for the Grand Cherokee Laredo is behind the glove box.
The Laredo has a single blend door motor located in the upper left hand corner behind the glove box. You have to fully open the glove box to see it. It is held in place with two Phillips screws and is easy to remove. To diagnose problems with the Laredo, examine the white axle that protrudes from the box when you remove the motor. First turn the axle and see if it is controlling the doors. You should see about 50degrees of rotation from stop point to stop point. Next examine the axle. There should be a pin molded onto the axle next to the heater box(like the comma on a "Q"). If this pin is broken, the full force of the actuator motor is being applied to the blend doors. This is a positive sign that the doors are either broken or will be very soon. HeaterTreater has a kit to replace the doors and return full functionality to the GC. You also need to check the operation of the re-circ door. Check online for instructions on how to check this problem. The re-circ door suffers from the same basic design flaw as the blend doors.