DTC P0171: System Too Lean (Bank 1); DTC P0172: System Too Rich (Bank 1) [01/2019 - 03/2019]: Wiring Diagram

WARNING: This page is about a different car, the 2022 Toyota Corolla, 2021 Toyota Corolla, 2020 Toyota Corolla, and 2019 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.

Refer to DTC P0031 for the air fuel ratio sensor circuit.
Refer to WIRING DIAGRAM
Refer to DTC P0102 for the mass air flow meter sub-assembly circuit.
Refer to WIRING DIAGRAM