The heated oxygen (HO2S) bank 1 sensor 1 is threaded into the cylinder 1, 3, 5 exhaust manifold (cylinders 1, 3, 5 are closest to front of dash). The sensor monitors the oxygen content in the exhaust gas before the pre-converter. The ECM supplies a variable output pump current to circuit 1667 in order to maintain a constant voltage level at the input pump current circuit 1665. As output pump current passes through the oxygen sensor when the sensor is operating above 300°C (572°F), the sensor will vary resistance according to changes in exhaust oxygen content. If oxygen content increases (lean air/fuel ratio) the resistance of the sensor increases which requires more current to maintain a constant voltage level. The ECM calculates a lambda value (actual air/fuel ratio divided by 14.6 to 1) based on the input pump current voltage level on circuit 1665 and the signal voltage level on circuit 412. DTC P0132 will set when the HO2S bank 1 sensor 1 lambda value exceeds a calibrated lambda offset value over a certain length of time.
DTC P0132 will set when the HO2S bank 1 sensor 1 lambda value exceeds a 0.03 lambda offset value when:
• | Condition exists for greater than 2 seconds |
• | Engine is running |
• | HO2S bank 1 sensor 2 diagnostics have run |
• | No HO2S bank 1 sensor 2 DTCs have been set |
DTC P0132 diagnostic runs continuously once the above conditions have been met.
P0132 is a (type B) DTC.
Bank 1 will default to open loop if this DTC is active.