P0161 Code: O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
🟢 Low severity · drivable
Safe to drive. This affects only the sensor's heater, which warms it faster after a cold start.
What P0161 means
The heater inside the bank 2 sensor 2 oxygen sensor is not working. Oxygen sensors have a small heater so they reach operating temperature quickly. When the heater circuit draws too little or too much current, the computer sets this code.
Symptoms
- Check engine light is on
- Failed emissions test
- Usually no noticeable driving symptoms
Common causes
- most common: Faulty oxygen sensor with a failed internal heater
- common: Blown fuse or damaged heater circuit wiring
- less common: Corroded or loose sensor connector
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Check the O2 sensor heater fuse and wiring | Yes | $0–20 |
| Replace the bank 2 sensor 2 oxygen sensor | Yes | $60–200 |
Frequently asked questions
Can I drive with a P0161 code?
Yes. It is a downstream sensor heater fault and won't affect drivability, though it may fail an emissions test until fixed.
What is the most common cause of P0161?
A faulty oxygen sensor whose internal heater has burned out.
How much does it cost to fix a P0161?
Typically $60–200 for a new sensor, or close to nothing if the problem is just a blown fuse.
Related codes
P0156
P0156 Code: O2 Sensor Circuit Malfunction (Bank 2 Sensor 2)
P0141P0141 Code: O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0160P0160 Code: O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 2)
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.