P0152 — O2 Sensor Circuit Low Voltage (Bank 2 Sensor 1)
Drive with caution — fix soon.
What P0152 means
This code means the front oxygen sensor on bank 2 is sending a persistently low voltage signal, which the computer interprets as a lean exhaust. It can stem from a failing O2 sensor, a short or open in the wiring, a vacuum or exhaust leak, or a genuine lean-running engine. It's a fairly common code and is usually fixable once the underlying cause is identified.
Common symptoms
- Check engine light is on
- Rough idle or slight engine shaking
- Reduced fuel economy
- Hesitation or mild loss of power
- Possible lean-mixture codes stored alongside it
Common causes
- Failing oxygen sensor (Bank 2 Sensor 1)
- Short to ground or open in the sensor signal wire
- Vacuum leak creating a genuine lean condition
- Exhaust leak upstream of the sensor
- Low fuel pressure or a dirty fuel injector
Typical repair cost
$150 – $500
Varies by vehicle and root cause.
Frequently asked questions
Can I keep driving with a P0152 code?
For short trips, usually yes, but don't rely on it indefinitely. This is the upstream sensor that helps set the fuel mixture, so a lasting fault can cause rough running and worse mileage. Have it diagnosed soon.
How much does it cost to fix a P0152 code?
Most fixes cost between $150 and $500. A straightforward oxygen sensor replacement is at the lower end, while tracking down a vacuum leak, exhaust leak, or fuel problem can push it higher.
Is a P0152 code serious?
It's a moderate-severity code. It usually won't strand you, but because it affects fuel control, leaving it unrepaired can lead to drivability issues and increased emissions.
What's the difference between P0151 and P0152?
Both involve a low signal from the same bank 2 upstream sensor, but P0151 is logged as a general circuit malfunction while P0152 specifically flags a low-voltage reading. In practice they overlap heavily and are diagnosed in a similar way.