Hi,
I have a 2010 TL. Passenger side mode door works, but the driver side is stuck on vent. Defrost and foot area does not work. I saw a B1239 code for "open or short for mode door control circuit." I followed the step by step instructions and I replaced the driver side mode door actuator from the dealer. Driver side still does not work, but now it throws a B1240 code "Problem with mode motor circuit, circuit, linkage". I replaced the driver side climate control unit and still no change and same B1240 code. I checked ground and continuity on the wiring from driver side climate unit to mode door actuator and they are good. What else is there to check? I saw that other modules (multiplex control unit, power seat, hands free and HIP) showed the same code; maybe one of those modules causing this problem? I unplugged the hands free module knowing this module goes bad, but nothing