Lexus DTC P1135 – Air/Fuel Ratio Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
DTC P1135 meaning on Lexus
DTC P1135 indicates a malfunction in the Air/Fuel Ratio Sensor Heater Circuit for Bank 1 Sensor 1 in a Lexus vehicle. This code specifically relates to the heating element circuit of the air/fuel ratio sensor located in the exhaust system before the catalytic converter.
Lexus DTC P1135 symptoms
Symptoms of DTC P1135 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 P1135 causes
Common causes of DTC P1135 in a Lexus include:
- Faulty air/fuel ratio sensor
- Issues with the sensor heater circuit wiring or connections
- Blown fuse related to the sensor heater circuit
Lexus DTC P1135 seriousness
DTC P1135 should not be ignored as it can lead to poor engine performance and increased emissions. Ignoring this code may result in further damage to the vehicle’s catalytic converter and other engine components.
How to diagnose DTC P1135 on Lexus
To diagnose DTC P1135 on a Lexus, a mechanic may perform the following steps:
- Use a scan tool to retrieve the specific fault code
- Inspect the wiring and connections related to the air/fuel ratio sensor heater circuit
- Check the sensor heater circuit fuse for continuity
- Test the air/fuel ratio sensor for proper operation
How to fix DTC P1135 on Lexus
To fix DTC P1135 on a Lexus, the following steps may be taken:
- Replace the faulty air/fuel ratio sensor if necessary
- Repair any damaged wiring or connections in the sensor heater circuit
- Replace the sensor heater circuit fuse if it is blown
- Clear the fault code and reset the Check Engine Light
How to erase DTC P1135 on Lexus
To erase DTC P1135 on a Lexus, the fault code can be cleared using a scan tool that has the capability to reset codes. Once the issue causing the fault code has been addressed and fixed, the code can be cleared, and the Check Engine Light should turn off.
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