Question

2007 Toyota Avalon XLS with engine code P0031, what is the meaning?

Answer 1

Hi there

DTC P0031 Oxygen (A/F) Sensor Heater Control Circuit Low (Bank 1 Sensor 1) 

This code is refferring to the O2 sensor on bank one BEFORE the catalytic converter. Typically over time the heater circuit fails inside the sensor and it has to be replaced. Bank 1 on this engine is the bank closest to the firewall.

Answer 2

P0031 TOYOTA - Oxygen Sensor Heater Control Circuit Low Bank 1 Sensor 1

Read more: https://www.autocodes.com/p0031_toyota.html