P0141

Diagnostic Chart:

Schematic:

The Heated Oxygen Sensor (HO2S sensor 2) is mounted behind the catalytic converter. This sensor is used to determine the oxygen storage capability of the catalytic converter. Oxygen storage capability is used as a measure of converter condition, and its ability to perform its function. Due to the location of the rear HO2S, it requires additional heat to operate properly. This sensor incorporates a heater, powered by ignition voltage which allows the sensor to remain functional under most operating conditions. In order to determine that the sensor heater is functioning, its function can only be tested after what is considered a cold start. The PCM will monitor airflow and the time it takes for the sensor to become functional. If a start up is considered to be a hot restart the heater function cannot be tested due to the amount of heat generated by the engine making it difficult to accurately diagnose a heater malfunction.

DTC PARAMETERS
DTC P0141 will set if the HO2S sensor 2 voltage remains between 303-599 mV for a calibrated time (based on start up coolant temperature) and:
^ Start up engine coolant temperature is less than 45°C (113°F).
^ Start up intake air temperature is less than 45°C (113°F).
^ The difference between engine coolant and intake air temperature is less than 7°C (13°F).
^ Engine has been running less than 255 seconds.
^ System voltage is between 11.6-16.0 volts.
^ HO2S Sensor 2 voltage was 395-491 mV at start-up.
^ DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0171, P0201, P0202, P0203, P0204, P0300, P0336, P0440, P0442, P0446, P0506, P0507, P0601, P0602 or P1441 are not set.

IMPORTANT: This diagnostic is ran only once per ignition cycle.

DIAGNOSTIC AIDS
Check for damaged wiring especially on HO2S Sensor 2 pigtail harness.