DTC Advanced Diagnostics: P0037: General Description
The rear secondary heated oxygen sensor (secondary HO2S (sensor 2)) heater is controlled by the duty signal command from the powertrain control module (PCM) to heat secondary HO2S (sensor 2) to an optimal temperature. The output driver circuit in the PCM monitors the voltage level of the SO2HT terminal, and if the voltage level of the SO2HTB1 terminal is ON (low voltage) despite the PCM outputs OFF signal to rear secondary HO2S (sensor 2), the PCM detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 5 seconds or more |
| DTC Type | Two drive cycles, MIL on |