On Board Diagnosis 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 before the three way catalyst (manifold) causes the longer switching time. To judge the malfunctions of heated oxygen sensor 2, ECM monitors whether the maximum voltage of the sensor is sufficiently high during the various driving condition such as fuel-cut.
DTC DETECTING CONDITION REFERENCE CHART
| DTC No. | Trouble diagnosis name | DTC detecting condition | Possible cause |
|---|---|---|---|
| P0137 0137 |
Heated oxygen sensor 2 circuit low voltage | The maximum voltage from the sensor is not reached to the specified voltage. |
|