Diagnostic Aids

After confirming DTC P0125, use Toyota hand-held tester or scan tool to access CURRENT DATA to confirm output voltage for heated oxygen sensor on each exhaust manifold (bank No. 1 sensor No. 1 and bank No. 2 sensor No. 1). If voltage displayed on scan tool is always less than 0.1 volt, heated oxygen sensor circuit may be open or shorted. Using hand-held tester or scan tool, read FREEZE FRAME data. Freeze frame data records engine conditions when malfunction is detected.