Lexus DTC P1155 – Air/Fuel Ratio Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
DTC P1155 meaning on Lexus
DTC P1155 indicates a malfunction in the Air/Fuel Ratio Sensor Heater Circuit for Bank 1 Sensor 1 in a Lexus vehicle. This code specifically points to an issue with the heating element circuit of the air/fuel ratio sensor located in the exhaust system.
Lexus DTC P1155 symptoms
Symptoms of DTC P1155 in a Lexus may include:
- Check Engine Light illuminated on the dashboard
- Decreased fuel efficiency
- Engine running rough or misfiring
- Reduced engine performance
Lexus DTC P1155 causes
Common causes of DTC P1155 in a Lexus include:
- Faulty air/fuel ratio sensor
- Issues with the sensor heater circuit wiring
- Corrosion or poor connections in the sensor circuit
- Defective Engine Control Module (ECM)
Lexus DTC P1155 seriousness
DTC P1155 should not be ignored as it can lead to poor engine performance and decreased fuel efficiency. Continuing to drive with this fault may cause further damage to the vehicle’s engine components.
How to diagnose DTC P1155 on Lexus
To diagnose DTC P1155 on a Lexus, a mechanic may perform the following steps:
- Use a diagnostic scanner to retrieve the fault code
- Inspect the wiring and connectors of the air/fuel ratio sensor
- Check the resistance of the sensor heater circuit
- Test the air/fuel ratio sensor for proper operation
How to fix DTC P1155 on Lexus
To fix DTC P1155 on a Lexus, the following steps may be taken:
- Replace the faulty air/fuel ratio sensor
- Repair any damaged wiring or connectors in the sensor circuit
- Clean or replace corroded connections
- If necessary, replace the Engine Control Module (ECM)
How to erase DTC P1155 on Lexus
To erase DTC P1155 on a Lexus, the fault code can be cleared using a diagnostic scanner. After the repair has been made, the scanner can be used to reset the Check Engine Light and clear the stored fault code from the vehicle’s memory.
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