Code result
P0161
O2 Sensor Heater Circuit Malfunction
Moderate severity
What it means
Same condition as P0141 but on the downstream sensor of bank 2. The sensor heater warms the element to operating temperature (~600 °C); without it the lambda sensor stays inactive in closed loop and the ECM cannot trim mixture.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Heater element open-circuit
highOne of the most commonly reported causes for this code — check this first.
Related help
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