P1135moderate severityPowertrain
Air/Fuel Sensor Heater Circuit Bank 1 Sensor 1
on 1992-2006 Lexus ES 300 3.0L V6 · FWD
What this code means
The heater circuit in the A/F sensor Bank 1 Sensor 1 is not performing correctly.
Symptoms
- CEL
- Poor cold-start economy
- Extended warm-up
- Failed emissions
Common causes
- Failed heater element
- Open/short in heater wiring
- Blown fuse
- Poor connector
Diagnostic steps
- Test heater resistance
- Check fuse
- Inspect wiring
- Test ECM heater driver
Repair notes
Replace A/F sensor or repair heater circuit.
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