Body, generic

B0205 HVAC Defroster Door Position

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

B0205 is absent from the published J2012 lists, and no carmaker documents it for the defroster door; a defrost door circuit has the code B0278. Saab files its 9-3 defrost door motor under B0240 06 and B0241 01, where an open, grounded or B+ shorted motor circuit leads to wrong air distribution. The defroster door sends air to the windscreen. MOTOR magazine notes that most electronic climate actuators report door position through a potentiometer driven by their gear train, as a signal of roughly 0 to 5 V. Older layouts get by without one: in Hitachi's CA1266779A a two-position actuator just flips the vent door between face vents and defroster, and US4819715A drives a shutter that opens either the upper vents or the defroster nozzle. A position fault means the door is not where it was commanded.

Likely causes

Defroster door actuator with stripped gears or worn feedback potentiometer
Door or linkage binding, broken or blocked by foreign objects
Position feedback or reference wire open or shorted

Symptoms

  • Little or no air reaches the windscreen in defrost mode
  • Air comes from the wrong outlets or a clicking noise is heard behind the dashboard

Repair estimate

DifficultyMediumDIY possible
Parts and labour€40–400
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

hvac defrost actuatorhvac control module

Related codes

B0278B0170B0150

References: motor.com, patents.google.com, patents.google.com, saabwisonline.com.