OBD-II code · Body

B0166 HVAC Discharge Air Temperature Sensor

The HVAC control module reports an implausible signal from the discharge (vent outlet) air temperature sensor. This sensor verifies that the actual outlet air temperature matches the commanded value.

Is it safe to drive with B0166?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyDischarge air temp sensor failed
  • PossibleWiring or connector fault

Symptoms

  • Warning light or symbol related to the affected system
  • Comfort or safety function impaired

Repair at a glance

Difficulty
Medium
DIY friendly
Often, with basic tools
Typical labour
0.5–2 h
Emissions test
Usually unaffected
Parts involved
Discharge Air Temp Sensor, HVAC Control Module

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.