Trouble Codes

P0141 O2 Sensor Heater Circuit Malfunction

Diagnostic Fault Code P0141

Failure of the HO2S heating element, sensor 2
The ECM detects that the HO2S heater is less than 0.30 A or greater than 2.5 A for more than 8 seconds.


Trouble code p0141 heated oxygen sensors (HO2S) are used to control fuel and monitoring after the catalytic converter. Each HO2S probe compares the oxygen content in the ambient air with the oxygen content in the exhaust stream. Each HO2S must reach the operating temperature to be able to provide an accurate voltage signal. The heating element inside each HO2S limits the time required to reach the operating temperature by the sensor. The heater voltage is supplied by the fuse circuit via the fuse. With the engine running, the heater’s mass is ensured by the HO2S low heater control circuit via the low voltage side controller built into the ECM. The ECM uses pulse width modulation (PWM) to control the HO2S heater to ensure the correct HO2S operating temperature. DTC P0141 set. May apply to such car brands as Toyota, Chevrolet, Ford, Nissan, Honda, GMC, Dodge, etc.

Possible causes of the fault

  • Erosion or broken wires may cause p0141 errors
  • Damage to the heater inside the lambda probe, measure with a multimeter the resistances on two wires of the same color coming out of the probe, should be about (4-10Ohm)
  • A short in the wires leading to the control module, measure the resistance and continuity of the circuits between the lambda probe connector and the control module
  • The combustion of the fuse in the heating circuit of the heated oxygen sensor can be caused by the heater of one of the probes. The problem may appear only after a certain time of probe operation. If there is no fault in the heating element circuit, monitor the amperage of each heating element using the scan tool to determine if one of the heating element elements is causing the fuse to break. Check that the sensor cable or beam is not in contact with the exhaust system.