OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Body generic / SAE

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.

SystemBody
Typegeneric / SAE
GroupB0
Range / number1 / 66

Possible causes

  • Discharge air temp sensor failed high
  • Wiring or connector fault medium

Symptoms

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

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 50–300 €
  • Estimated time: 0.5–2 h
  • Component: discharge air temp sensor
  • Component: hvac control module

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication