P2197 — O2 Sensor Signal Biased/Stuck Lean Bank 2 Sensor 1

P2197: O2 Sensor Signal Biased/Stuck Lean Bank 2 Sensor 1 — what it means, the affected system and what to check before replacing parts.

Meaning, symptoms, causes and checks

O2 Sensor Signal Biased/Stuck Lean Bank 2 Sensor 1. Basic catalogue definition; diagnostic details have not yet been reviewed.

Affected system: Powertrain

Symptoms

  • The engine warning lamp may illuminate.
  • Hesitation, irregular operation or reduced response may accompany the fault.

Possible causes

  • A fault in the bank 2 upstream oxygen sensor, its wiring or connector may hold the reported signal lean.
  • Intake or upstream exhaust leakage and insufficient fuel delivery may also explain a persistent lean indication.

What to check

  • Confirm bank 2 sensor 1 and inspect its connector and wiring for corrosion or damage.
  • Review its live readings together with fuel trims and related codes; do not equate the sensor indication with a confirmed lean mixture.
  • Inspect intake and exhaust leaks and evaluate fuel delivery before condemning the oxygen sensor.

Also written as: P2197-00, P219700 (some scan tools add the fault-type byte, e.g. -00).