FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0053



P0053 - HO2S Heater Resistance (B1/S1)






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. The HO2S requires a minimum temperature to operate properly and provide a closed loop fuel control system. The HO2S contains the heater element to reduce its warming-up time and ensure its performance during all driving conditions. The ECM controls this heater element by duty cycle. The main relay supplies voltage to the heater and the ECM provides a ground circuit for activating the heater.

DTC Description
The heater current difference between heater off and on is less than threshold value, the ECM determines that a fault exists and a DTC is stored.


Detecting Condition and Specifications





Wiring Schematic





Signal Waveform