P2252

P2252 - HO2S Reference Ground Circuit Low






General Description
In order to control emissions of the CO, HC and NOx components of the exhaust gas, heated oxygen sensor (HO2S), mounted on the front side and rear side of catalytic converter, detects the oxygen content in the exhaust gas. The front HO2S signal is used to control air/fuel ratio (closed loop fuel control) and the rear HO2S signal is used to monitor front HO2S and catalyst for proper operation.

DTC Description
ECM sets DTC P2252 if the ECM detects reference ground voltage remains excessively low for a predetermined time (open or short to ground in reference ground circuit).

Detecting Condition





Wiring Schematic





Signal Waveform