Audi DTC P1118 – O2 Sensor Heater Circuit, Bank1-Sensor2 Open
DTC P1118 meaning on Audi
The DTC P1118 on an Audi indicates an issue with the O2 sensor heater circuit for Bank 1, Sensor 2. This means that the heating element in the downstream oxygen sensor located after the catalytic converter on the first bank of cylinders is not functioning properly.
Audi DTC P1118 symptoms
Common symptoms of a P1118 DTC on an Audi may include poor fuel economy, rough idling, hesitation during acceleration, and an illuminated check engine light on the dashboard.
Audi DTC P1118 causes
The P1118 DTC on an Audi can be caused by a faulty O2 sensor, damaged wiring or connectors in the sensor circuit, a blown fuse, or a problem with the engine control module (ECM).
Audi DTC P1118 seriousness
While the vehicle may still be operable with a P1118 DTC, it is important to address the issue promptly to prevent potential damage to the catalytic converter and ensure optimal engine performance and fuel efficiency.
How to diagnose DTC P1118 on Audi
To diagnose a P1118 DTC on an Audi, a mechanic would typically use a scan tool to retrieve the fault code and then perform a visual inspection of the O2 sensor and its wiring. They may also test the sensor’s resistance and check for proper voltage supply to the heater circuit.
How to fix DTC P1118 on Audi
To fix a P1118 DTC on an Audi, the faulty O2 sensor heater circuit components need to be identified and replaced if necessary. This may involve replacing the O2 sensor itself, repairing damaged wiring or connectors, or replacing a blown fuse. Once the issue is resolved, the DTC should be cleared from the ECM.
How to erase DTC P1118 on Audi
To erase a P1118 DTC on an Audi, a scan tool can be used to clear the fault code from the engine control module’s memory. After the repair has been completed and the issue resolved, clearing the DTC will turn off the check engine light and ensure that the vehicle’s onboard diagnostics system is reset.
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