P1109 Fault Code
You can find information about the P1109 fault code on this page.
BE WARNED! This particular code can mean a different thing depending on what make the car is, check below.
Manufacturer-Specific Meanings
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Detailed Manufacturer-Specific Explanations
Audi – OXYGEN SENSOR CIRCUIT, BANK 2 SENSOR 2 – VOLTAGE TOO LOW/AIR LEAK
For Audi, fault code P1109 is logged when the powertrain control module (PCM) has detected an issue with the second oxygen sensor in bank 2 of the engine.
Oxygen sensors are used to monitor the air-fuel ratio found in the exhaust system.
When too little oxygen is detected, it signals a low voltage output to the ECU. These sensors help determine the level of emissions that are being produced by the engine.
This fault code means that either the air-fuel mixture coming from the engine is incorrect or that there is an air leak somewhere upstream of the exhaust system. It can also mean components in the exhaust system are faulty.
Sensor 2 is the oxygen sensor that is found downstream of the catalytic converter. Bank 2 refers to the side of the engine where cylinder 1 is located.
See generic codes: P0151
Citroën – IAT – B SENSOR INTERMITTENT
For Citroen, fault code P1109 is logged when the powertrain control module (PCM) has detected an issue with the intake air temperature (IAT) B sensor. This happens when the signal from the IAT sensor to the PCM is intermittent or erratic.
The IAT sensor is responsible for relaying information about the air entering the engine to the PCM. This is done to allow for adjustments to the air-fuel mixture for optimization.
Temperature is a fundamental aspect of thermodynamics. Variations in the temperature of the intake air mean that the thermodynamic properties of the air entering the combustion chamber change.
The IAT sensor provides valuable information to the ECM regarding the incoming air temperature. This allows the PCM to adjust the air-fuel mixture accordingly to allow for optimal efficiency and operation.
An intermittent signal from the IAT sensor will likely result in decreased performance of the vehicle as the PCM is unable to properly optimize.
See generic codes: P0114
Ford – IAT – B SENSOR INTERMITTENT
For Citroen, Ford, and Peugeot, fault code P1109 represents the same issue. For more information on the problem and similar generic fault codes, please see the above description for Citroen.
See generic codes: P0114
Peugeot – IAT – B SENSOR INTERMITTENT
For Citroen, Ford, and Peugeot, fault code P1109 represents the same issue. For more information on the problem and similar generic fault codes, please see the above description for Citroen.
See generic codes: P0114
Volkswagen – OXYGEN SENSOR CIRCUIT, BANK 2 SENSOR 2 – VOLTAGE TOO LOW/AIR LEAK
For Audi, Volkswagen, and Volvo, fault code P1109 represents the same issue. For more information on the problem and similar generic fault codes, please see the above description for Audi.
See generic codes: P0151
Volvo – OXYGEN SENSOR CIRCUIT, BANK 2 SENSOR 2 – VOLTAGE TOO LOW/AIR LEAK
For Audi, Volkswagen, and Volvo, fault code P1109 represents the same issue. For more information on the problem and similar generic fault codes, please see the above description for Audi.
See generic codes: P0151
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