TorqueMech OBD Code Guide
P0137 - O2 Sensor Circuit Low Voltage (Bank 1 Sensor 2)
Downstream O2 sensor signal voltage low (B1S2).
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Code Overview
Downstream O2 sensor signal voltage low (B1S2).
Common Causes
- O2 sensor failure
- Wiring issue
- Exhaust leak
- Lean condition
Diagnostic Steps
- Inspect exhaust for leaks
- Inspect sensor wiring
- Verify activity on scan tool
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Next Steps
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