P1121 – Audi DTC

Audi DTC P1121 – O2 Sensor Heater Circuit, Bank2-Sensor2 Short to Ground

DTC P1121 meaning on Audi

DTC P1121 on an Audi indicates an issue with the O2 sensor heater circuit for Bank 2, Sensor 2. This fault code specifically points to a short to ground in the heater circuit of the downstream oxygen sensor located after the catalytic converter on bank 2 of the engine.

Audi DTC P1121 symptoms

Symptoms of DTC P1121 on an Audi may include:

• Check Engine Light (CEL) illuminated on the dashboard
• Decreased fuel efficiency
• Engine running rough or misfiring
• Reduced engine performance

Audi DTC P1121 causes

The common causes of DTC P1121 on an Audi are:

• Short to ground in the O2 sensor heater circuit for Bank 2, Sensor 2
• Wiring or connector issues in the O2 sensor circuit
• Failed O2 sensor heater element

Audi DTC P1121 seriousness

While DTC P1121 may not cause immediate drivability issues, it is important to address this fault code promptly to prevent potential damage to the catalytic converter and ensure optimal engine performance and emissions control.

How to diagnose DTC P1121 on Audi

To diagnose DTC P1121 on an Audi, follow these steps:

1. Use an OBD-II scanner to retrieve the fault code and verify it is P1121.
2. Inspect the wiring and connectors in the O2 sensor heater circuit for Bank 2, Sensor 2 for any visible damage or corrosion.
3. Check the resistance of the O2 sensor heater element to determine if it is within specifications.
4. Perform a continuity test on the O2 sensor heater circuit to identify any short to ground.

How to fix DTC P1121 on Audi

To fix DTC P1121 on an Audi, consider the following steps:

1. Repair any damaged wiring or connectors in the O2 sensor heater circuit for Bank 2, Sensor 2.
2. Replace the O2 sensor if the heater element is found to be faulty.
3. Clear the fault code using an OBD-II scanner after completing the repairs.

How to erase DTC P1121 on Audi

To erase DTC P1121 on an Audi:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Access the scanner’s menu to clear the fault codes stored in the ECU.
3. Follow the on-screen prompts to erase the DTC P1121 code.

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