Audi DTC P1120 – O2 Sensor Heater Circuit, Bank2-Sensor1 Open
DTC P1120 meaning on Audi
The DTC P1120 on an Audi indicates an issue with the O2 sensor heater circuit for Bank 2, Sensor 1. This means that the heating element in the oxygen sensor located in the exhaust system before the catalytic converter on the second bank of cylinders is not functioning properly.
Audi DTC P1120 symptoms
Common symptoms of the DTC P1120 on an Audi may include:
- Check Engine Light illuminated on the dashboard
- Poor fuel economy
- Engine running rough or misfiring
- Reduced engine performance
Audi DTC P1120 causes
The DTC P1120 on an Audi can be caused by various factors, including:
- Faulty O2 sensor heater circuit
- Wiring or connector issues in the O2 sensor circuit
- Blown fuse related to the O2 sensor heater
- Internal ECM (Engine Control Module) fault
Audi DTC P1120 seriousness
While the DTC P1120 may not cause immediate drivability issues, it is important to address this problem promptly to prevent potential damage to the catalytic converter and ensure optimal engine performance and emissions control.
How to diagnose DTC P1120 on Audi
To diagnose the DTC P1120 on an Audi, a mechanic may perform the following steps:
- Use an OBD-II scanner to retrieve the fault code and freeze frame data
- Inspect the wiring and connectors related to the Bank 2, Sensor 1 O2 sensor
- Check the O2 sensor heater circuit for continuity and proper voltage
- Test the O2 sensor heater resistance
- Verify the integrity of the fuse related to the O2 sensor heater
How to fix DTC P1120 on Audi
To fix the DTC P1120 on an Audi, the following steps may be taken:
- Replace the faulty Bank 2, Sensor 1 O2 sensor
- Repair any damaged wiring or connectors in the O2 sensor circuit
- Replace the blown fuse if necessary
- If the ECM is determined to be faulty, it may need to be reprogrammed or replaced
How to erase DTC P1120 on Audi
After addressing the underlying issue causing the DTC P1120 on an Audi, the fault code can be cleared using an OBD-II scanner. This will reset the Check Engine Light and erase the diagnostic trouble code from the vehicle’s memory.
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