P0139
O2 Sensor Circuit Slow Response Bank 1 Sensor 2
2020-2024 Citroën C4 Electric 🇩🇪
Low SeverityPowertrain
Description
The downstream O2 sensor on Bank 1 is responding too slowly.
Symptoms
- Check Engine Light
- Failed emissions
Common Causes
- Aging sensor
- Contaminated sensor
- Catalyst issue
Diagnostic Steps
- Monitor sensor response
- Check catalyst efficiency
Repair Notes
Replace downstream O2 sensor.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P0139 on Other Vehicles
Citroën Berlingo
2018-2024 1.2L I3 PureTech
Citroën Berlingo
2018-2024 1.5L I4 BlueHDi
Citroën Berlingo
2018-2025 1.2L I3 Turbo PureTech 110
Citroën Berlingo III FR
2018-2025 1.2L I3 Turbo PureTech 110
Citroën C1 III
2014-2022 1.0L I3 VTi 72
Citroën C1 III
2014-2022 1.2L I3 PureTech 82
Citroën C3
2016-2024 1.2L I3 PureTech
Citroën C3
2016-2024 1.5L I4 BlueHDi
Common Questions
What does code P0139 mean on a 2020-2024 Citroën C4?
P0139 stands for "O2 Sensor Circuit Slow Response Bank 1 Sensor 2". The downstream O2 sensor on Bank 1 is responding too slowly.
What are the symptoms of P0139 on a Citroën C4?
Common symptoms of P0139 include: Check Engine Light, Failed emissions.
What causes P0139 on a 2020-2024 Citroën C4?
Common causes of P0139 include: Aging sensor, Contaminated sensor, Catalyst issue.