P0137 — O2 Sensor Circuit Low Voltage (Bank 1 Sensor 2)
Category: Powertrain Severity: Low
Updated:
DTC code P0137 means: O2 Sensor Circuit Low Voltage (Bank 1 Sensor 2). It falls under the "Powertrain" category, with an estimated severity of Low. Common causes include faulty downstream O2 sensor, exhaust leak near the downstream sensor and signal wire shorted to ground; it's worth confirming the diagnosis before replacing parts.
Possible causes
- Faulty downstream O2 sensor
- Exhaust leak near the downstream sensor
- Signal wire shorted to ground
- Badly worn catalytic converter
Symptoms
- Check engine light
- No drivability symptoms
- May fail an emissions test
How to diagnose it step by step
- Look for exhaust leaks.
- Watch the sensor 2 signal.
- Check the wiring.
- Replace the sensor.
How to fix it
The downstream sensor should read fairly steady (0.5–0.7 V when warm). If it is always low, look for exhaust leaks, then replace the sensor.
Estimated repair cost
Downstream sensor: $100–280.
Frequently asked questions
What does DTC code P0137 mean?
O2 Sensor Circuit Low Voltage (Bank 1 Sensor 2).
Is code P0137 serious?
Severity Low. Usually a minor fault; check the causes listed.
Can I keep driving with code P0137?
Yes, you can drive normally.
Related codes
P0136 P0138 P0135 P0139 P0134 P0133 P0132 P0131 P0130 P0140
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