Temporarily Fixing a Broken HVAC Mode Door on a Saturn L300
This winter, the mode door on the 2002 Saturn L300 started to behave erratically. It was only blowing air out of the defrost vents. Since it was winter, this was the preferred location, and we let it be. As someone who doesn’t drive the car regularly, I forgot it was broken. Now, let’s fast forward to last weekend, the hottest days of 2023. I was reminded that the dashboard vents did not blow air anymore. Online research suggested looking at the mode door actuator and that, most likely, a gear was worn or split inside the actuator. Visual inspection did indeed show that the gear was slipping and not turning the mode door through all five positions. I removed the actuator and manually rotated the cam to turn the mode door axle so the air would flow through the front dashboard vents. While this fix will work for the summer when we don’t need the defrost, it will not work when it is colder. I opened the actuator, and the gear to drive the axle for the mode door was split. The Saturn is ol...