Hours: 07–23 daily

TuningBot DTC Database · v4.37.15

P2249 Heated oxygen sensor (HO2S) 1, bank 2, reference voltage - circuit low

Generic (OBD-II) interpretation in the TuningBot DTC database.

P · PowertrainEmissionsOBD2

What P2249 means

P2249
Heated oxygen sensor (HO2S) 1, bank 2, reference voltage - circuit low Generic · emissions Data confidence 85%

The control module detected that the signal in the Heated oxygen sensor (HO2S) 1, bank 2, reference voltage circuit stayed below the expected operating range.

Symptoms

  • MIL illuminated
  • Possible increased fuel consumption
  • Possible unstable idle

Possible causes

  • Wiring short to ground
  • H025

Recommended checks

  • Read live sensor voltage/current and heater status
  • Inspect wiring and connectors
  • Check for exhaust leaks near the sensor
  • Check fuel trim values for upstream mixture faults

Related and nearby codes

How to read P2249

P

Powertrain: engine, transmission and driveline systems.

2

Generic SAE-standard code: same meaning on every make.

249

Specific fault index within the subsystem.

Frequently asked questions about P2249

What does P2249 mean?

Heated oxygen sensor (HO2S) 1, bank 2, reference voltage - circuit low. The control module detected that the signal in the Heated oxygen sensor (HO2S) 1, bank 2, reference voltage circuit stayed below the expected operating range.

Is P2249 generic or manufacturer-specific?

P2249 is a generic OBD-II code: it has the same meaning on every make and model that follows the SAE standard.

Can TuningBot remove P2249 at file level?

If the fault logic lives in the ECU calibration, yes: our DTC Removal file service disables the specific fault entry. Checksum correction is not included: it is a separate, optional service. Not sure whether your case qualifies? Request a free assessment and our engineers will check your ECU file.

Other file services

ECU tuningDyno-tested results by model and engine See the results →

← Search the full DTC database