Diagnostic Trouble Code (DTC) Information ECM-252D
Condition
The engine control module (ECM) monitors the aging of the front heated oxygen sensor (HO2S) by checking its ability to react to changes in the exhaust gases. The diagnostic trouble code (DTC) is stored if the engine control module (ECM) registers that the heated oxygen sensor (HO2S) reacts too slowly to changes in the fuel/air mixture.
Substitute Value
- Three-way catalytic converter (TWC) diagnostics are disabled.
Possible Source
- The cables for the calibration current and the pump current are short-circuited to each other
- Open-circuit in signal cable (-)
- Open-circuit in the cable for calibration current
- Damaged front heated oxygen sensor (HO2S).
Fault symptom[s]
- Malfunction indicator lamp (MIL) lit.