Error code

OBD2 P0137

OBD2P0137
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.

What it means

O2 Sensor Circuit Low Voltage.

Severity

moderateCan drive, but should address the issue soon as it affects emissions.

Summary

P0137 indicates low voltage in the heated oxygen sensor (HO2S) circuit for Bank 1 Sensor 2, which is located after the catalytic converter.

Common Causes

  • Faulty HO2S sensor
  • Circuit fault due to damaged wire harness or connectors
  • Exhaust leak between the TWC and HO2S

Diagnosis

  1. Check fuses and harnesses for any obvious problems.
  2. Inspect oxygen sensors for damage or corrosion.
  3. Use a mechanic's stethoscope to check for exhaust leaks.
  4. Disconnect ECM and HO2S, then test circuit continuity and resistance.

Fixes

  • Replace the faulty sensor if internal resistance is below 10 kΩ.

FAQ

What does P0137 mean?

P0137 indicates low voltage in the heated oxygen sensor circuit for Bank 1 Sensor 2, which is used to monitor catalytic converter performance.

How do I fix P0137?

First diagnose and repair any wiring or connector issues. If no problems are found, replace the faulty HO2S sensor.

Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.