Error Code B1340 & B1344 Air Mix Door

1998 Cadillac STS V8

I guess I got this done, let me know?

Not sure how this is going to help me. BUT lets start with the driver side door issue first. May I state again, I can clearly hear a gearing noise coming underneath the driver side dash NOT by the gas pedal\center consul but on the other side by the PARKING BRAKE. Is this "left MIX door actuator" that is mentioned by basscatt above? If so, how do you get to it. Remove the Parking Brake assembly?

Also, let me mention two things. 1 the HVAC system does work. Heat and AC work properly. Vents do change but I will try again. I live in Phoenix, never any need for heat. AC works fine. 2 my battery keeps going dead. I had AutoZone check out the system and it is all okay. Now, I see reading the suggested links, that this Mix Door Actuator can lead to power loss. I can say for certain that when I turn the car off, I continue to hear the gearing sounds coming from under the dash board. Could this be Mix Door issue lead to draining the battery?

Basscatt, I am getting back to this only now. I did what you suggested with twist, after disconnecting both terminals battery good, I only attached the under the hood, Battery DEAD. Disconnected that and connected inside rear seat and Battery GOOD. Something going on with an under the hood fuse box connections. I believe the HVAC runs off that so I am going to deal with the Air Door Mix next and sees if that corrects the issue. Will be looking at that sensor fan also.

FYI: I did tweak my back the other week and was waiting for it to clear up before going upside down under the dash board. BTW: with my STS, Does the radio cover just pop off like the Deville? to assist with the door mix install.