DTC P0036: Ho2S Heater Control Circuit (Sensor 2): Description
WARNING: This page is about a different car, the 2002 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
The Heated Oxygen Sensor (HO2S) heater is a device used to reduce the time that the sensor takes to go active. The HO2S ban 1 sensor 2 heater helps maintain proper sensor temperature for catalyst testing, and fuel trim adjustments. The heater receives power through a fused ignition circuit. The Powertrain Control Module (PCM) uses a low side driver ODM to turn the heater ON and OFF. The PCM monitors the circuit for conditions that are incorrect for the commanded state of the low side driver. If the PCM detects an incorrect circuit conditions, this DTC will set.