P0152 O2 Sensor Circuit High Voltage Bank 2 Sensor 1

P0152 indicates high voltage on the bank 2 sensor 1 oxygen-sensor circuit. The upstream bank 2 signal is higher than expected or stuck rich.

Code details

Generic OBD-II · P0

System: Fuel / Air
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not treat P0152 as a catalyst fault; start with upstream sensor circuit behavior and rich-condition causes.

Symptoms of P0152

Check-engine light on, sometimes with rough or uneven running.
Hesitation, surging, or a noticeable change in fuel economy.
Occasionally hard starting or a smell of unburnt fuel.

Common causes of P0152

A failing or contaminated sensor (MAF, MAP, oxygen or air-fuel sensor).
Intake or vacuum leaks, or an exhaust leak near an upstream sensor.
Wiring, connector, or fuel-delivery problems that skew the reading.

Useful checks before replacing parts

Review bank 2 fuel trims, fuel pressure, purge flow, injector leakage, and rich-running symptoms before replacing the sensor.
Inspect signal wiring for short-to-voltage, poor connector condition, and contamination that can bias the signal high.
Compare bank 2 sensor response during a controlled lean change to see whether the signal moves normally.

Related OBD-II codes

These nearby fuel / air entries can help compare wording and pin down the fault area.