P0156Low urgency
O2 Sensor Circuit (Bank 2 Sensor 2)
Emission · Oxygen Sensors
✅ Safe to drive. Required for catalyst monitoring and emissions testing. Fix within 2–3 weeks.
What this means
The downstream Bank 2 oxygen sensor circuit has a fault. The downstream Bank 2 sensor monitors the Bank 2 catalytic converter efficiency.
Likely causes
- Failed downstream Bank 2 O2 sensorMost common
- Wiring fault or corroded connectorCommon
Estimated repair cost
Downstream O2 sensor$80 – $250
Wiring/connector repair$80 – $200
🏪
Sponsored · Local Shop
Find shops near you specializing in this repair
Get quotes from certified mechanics · Free estimates
📦
Sponsored · Parts (Amazon affiliate)
Shop parts commonly used for this repair
Amazon search results for this code · prices and availability vary
Sponsored: MyOBDCode may earn compensation when you click partner links on this page.
Frequently asked questions about P0156
What does P0156 mean?
The downstream Bank 2 oxygen sensor circuit has a fault. The downstream Bank 2 sensor monitors the Bank 2 catalytic converter efficiency.
Is P0156 serious?
Safe to drive. Required for catalyst monitoring and emissions testing. Fix within 2–3 weeks.
How much does it cost to fix P0156?
Repair costs for P0156 range from $80 – $250 depending on the root cause and your vehicle.
Can I drive with P0156?
Yes, the vehicle is safe to drive. Schedule a repair at your convenience.