OBD Codes List

Diagnostic reference · P2A04

P2A04

O2 Sensor Circuit Range/Performance Bank 2 Sensor 2

System
Powertrain control (P code)
Lamp
Check Engine Light
Category
Powertrain - Fuel/Air Metering

What it means

P2A04 means O2 Sensor Circuit Range/Performance Bank 2 Sensor 2.

Where it lives

For P2A04, the description names the sensor as the part involved. The description of P2A04 puts it on bank 2.

Check these first

  • A slow or lazy bank 2 sensor 2 oxygen sensor
  • A contaminated bank 2 sensor 2 oxygen sensor
  • An exhaust leak ahead of bank 2 sensor 2
  • High resistance in the bank 2 sensor 2 signal wire
  • A rich or lean mixture skewing bank 2 sensor 2

What to do next

  1. Read bank 2 sensor 2 oxygen sensor voltage on a scan tool
  2. Watch bank 2 sensor 2 switching through a drive cycle
  3. Inspect the exhaust ahead of bank 2 sensor 2 for leaks
  4. Test the bank 2 sensor 2 signal circuit for resistance
  5. Replace the bank 2 sensor 2 oxygen sensor if it stays lazy
  6. Clear the code and retest

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Updated

Generic SAE J2012 definition. Last updated 2026-10-10.