Hey guys- new here and this may have been answered before so I apologize if so. I have an 09 Titan Pro-4x. It is currently not wanting to go into 4x4. All the sounds sound normal and my dash readout is there. I have had multiple shop tell me actuator motor and then those that say no because the dash readout is there. No warning lights. It just acts like its not getting communication to front tires to engage. I can get it to switch back and forth on dash with controls like normal and sounds normal but it wont allow go back to 2wd after doing so at random. Any ideas? Sensor? Vacuum leak? Actuator motor? Or something totally different. I just don't want ripped off at a service center. I must add just in case its important that the vehicle I sat undrove for a couple months before this happened.