P0136moderate severityPowertrain
O2 Sensor Circuit Bank 1 Sensor 2
on 1997 Dodge Ram Van 3.9L V6 · RWD
What this code means
General malfunction in the downstream O2 sensor circuit for Bank 1.
Symptoms
- Check Engine Light
- Failed emissions test
- Reduced catalyst monitoring
Common causes
- Faulty downstream O2 sensor
- Wiring damage
- Exhaust leak after catalyst
Diagnostic steps
- Test O2 sensor voltage
- Inspect wiring
- Check for exhaust leaks after cat
Repair notes
Replace downstream O2 sensor.
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