B1231 Code: Meaning, Causes, and Symptoms | OBD2 Codes

B1231 – Open In The Evaporator Temperature Sensor Circuit

 

B1231 Possible Symptoms

 

Engine Light ON (or Service Engine Soon Warning Light)

 

B1231 Possible Causes

 

Faulty Evaporator Temperature Sensor,Evaporator Temperature Sensor harness is open or shorted,Evaporator Temperature Sensor circuit poor electrical connection,Faulty Climate Control Unit

 

B1231 Description

 

The Climate Control Unit monitors the Evaporator Temperature Sensor. The Climate Control Unit sets the OBDII code when the Evaporator Temperature Sensor is not to factory specifications.