B0179 Code: Meaning, Causes, and Symptoms | OBD2 Codes

B0179 – Output Air Temperature Sensor 2 Circuit Range/Performance

 

B0179 Possible Symptoms

 

Engine Light ON (or Service Engine Soon Warning Light)

 

B0179 Possible Causes

 

Faulty Output Air Temperature Sensor 2,Output Air Temperature Sensor 2 harness is open or shorted,Output Air Temperature Sensor 2 circuit poor electrical connection,Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module

 

B0179 Description

 

Air temperature sensors allow the Heating, Ventilation, and Air Conditioning (HVAC) Control Module to monitor the discharge duct air, outside air and inside air temperatures. The HVAC control module provides ground to the air temperature sensor through the low reference circuit. The HVAC control module monitors the voltage drop across the air temperature sensor thermistor by supplying a 5 volt reference to the signal circuit of the air temperature sensor for automatic control calculations. When the air temperatures are cold, the resistances of the sensors are high and the voltage signals are high. When the air temperatures are hot, the resistances of the sensors are low and the voltage signals are low. The HVAC control module can read voltage values and count values where 1 volt is approximately equal to 51 counts.