B0166HVAC Discharge Air Temperature Sensor
- Generic OBD-II code · Body
- How the car detects it
- The public J2012 lists do not contain B0166, and no make describes it as a discharge air sensor. Saab does use it, for the cabin rather than the outlet: in 9-3 climate control manuals from 2003 to 2012, B0166 05 marks the indoor or compartment temperature sensor as open or shorted to supply once the module input rises above 4.8 V, checked continuously with the ignition on; B0165 02 is the matching short to ground. Discharge or duct air sensors are NTC thermistors in the outlet ducts that let the module check what it actually delivers. GM's Global A system, per the 2011 Saab 9-5 manual, numbers them B0173, B0178, B0509 and B0514. A B0166 therefore needs the make's own definition.
- What you may notice
- Automatic climate control misjudges cabin or outlet temperature and over- or undercorrects
- Set temperature is not held steadily
- Likely causes
- LikelySensor open or signal shorted to supply (Saab 9-3 cabin sensor)
- PossibleSensor connector loose or left unplugged after dashboard work
- RareOn other makes, the outlet duct sensor itself failed
- Repair
- Medium · Often possible to do yourself.Typical cost: €30 – €250
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.