Detection Condition

DTC P1132 (Bank 1) and P1152 (Bank 2) indicates HO2S is indicating rich at the end of a test, trying to correct for over-lean conditions. The test fails when fuel control system no longer detects a switch for a calibrated amount of time.

HO2S detects presence of oxygen in the exhaust and produces a variable voltage according to the amount of oxygen detected. A high concentration of oxygen in the exhaust produces a low voltage signal (less than 0.4 volt). A low concentration of oxygen in the exhaust produces a high voltage signal (more than 0.6 volt). HO2S provides feedback to PCM indicating air/fuel ratio in order to achieve near stoichiometric air/fuel ratio of 14.7:1 during closed loop engine operation.