DTC Detection Logic
The heated oxygen sensor 2 has a much longer switching time between rich and lean than the air fuel ratio (A/F) sensor 1. The oxygen storage capacity of the three way catalyst 1 causes the longer switching time. To judge malfunctions of heated oxygen sensor 2, ECM monitors whether the maximum voltage of the sensor is sufficiently high during various driving conditions such as fuel-cut.
| DTC No. | Trouble diagnosis name (Trouble diagnosis content) | DTC detecting condition | Possible cause |
|---|---|---|---|
| P0137 | HO2S2 (B1) [Heated oxygen sensor 2 (bank 1) circuit low voltage] | The maximum voltage from the sensor does not reach the specified voltage. |
|
| P0157 | HO2S2 (B2) [Heated oxygen sensor 2 (bank 2) circuit low voltage] |