All codes › P0161
P0161: O2 Sensor Heater Circuit (Bank 2 Sensor 2)
What it means
The heater circuit in the bank 2 downstream O2 sensor has failed.
Severity: Low Emissions only.
Common causes
- Burned-out heater
- Blown fuse
- Wiring damage
- Connector fault
Most common causes first. Exact causes vary by make, model and engine.
Can I fix it myself?
Often DIY. Bank 2 downstream sensor is usually reachable from under the car.
Repair cost
SEEDED ESTIMATE Roughly $70–$330
Most likely repair: oxygen sensor. Diagnosis fees, taxes and other causes are not included.
| Line | Low | High | Basis |
|---|---|---|---|
| Oxygen sensor | $36 | $168 | Typical listed retail range, source |
| Labor 0.3–1 hr | $30 | $160 | $100–$160/hr, shop survey |
⚠️ This is an editorial placeholder range for this type of repair. It is not based on real invoices or licensed pricing data yet. Real ranges will appear here once enough reader invoices for P0161 are verified.
Verified reader invoices for P0161: 0. Share your repair bill to help build real costs.
Tools that can read P0161
- ScanFixAI: Pro $29.99/mo or $249.99/yr
- OBDAI: Annual PRO bundle $299
- BlueDriver Pro Next-Gen: $119.95 list ($99.95 sale seen)
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