Failed O2 sensor heater element. Blown fuse for O2 heater circuit. Corroded connector. Wiring open circuit or short. ECM driver fault (rare).

Which cars are affected by P0135?

P0135 is most commonly reported on Toyota, Honda, Ford, Vauxhall, Nissan vehicles, but can appear on any make.

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P0135

Low severity

O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1)

The heater element in the upstream O2 sensor on bank 1 has failed or its circuit has a fault. The heater brings the sensor to operating temperature quickly after a cold start.

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Common causes of P0135

1Failed O2 sensor heater element

2Blown fuse for O2 heater circuit

3Corroded connector

+2 more causes

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Commonly affected vehicles

ToyotaHondaFordVauxhallNissan

P0135 can appear on any vehicle — these are the makes where it is most frequently reported.

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Related fault codes

P0171Medium

System Too Lean (Bank 1)

P0300High

Random/Multiple Cylinder Misfire Detected

P0420Medium

Catalyst System Efficiency Below Threshold (Bank 1)

P0172Medium

System Too Rich (Bank 1)