P0059 HO2S Heater Resistance Bank 2 Sensor 1

P0059 points to heater resistance outside limits for bank 2 sensor 1. The upstream heater circuit on bank 2 is not within expected range.

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 assume a fuel trim problem is sensor-response related until the upstream heater resistance fault is resolved.

Symptoms of P0059

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 P0059

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

Check bank 2 sensor 1 heater resistance, feed voltage, driver control, ground integrity, fuse supply, and connector condition.
Inspect wiring near exhaust manifolds, heat shields, sensor connectors, rubbed insulation, and shared heater circuits for damage.
Compare heater command with sensor warm-up speed, fuel-control readiness, and companion bank 2 oxygen sensor codes.

Related OBD-II codes

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