What P0135 means
02 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
Common causes (general)
Before spending money on parts, verify the code with a scan tool and read freeze frame data. Freeze frame captures every sensor value at the moment the code set — this is often enough to figure out the root cause without further testing.
Manufacturer-specific descriptions
Different manufacturers use this code for slightly different failure modes. Here's what your specific make means by P0135:
| AUDI | Defective Oxygen Sensor/Air Fuel Ratio Sensor, defective Oxygen Sensor/Air Fuel Ratio Sensor Heater Circuit, Exhaust System Leak, Intake Air System leak, Low Fuel Pressure, Defective Engine Coolant Temperature Sensor, Defective sensor wiring and or circuit problem, PCM software needs to be updated, Defective PCM |
| BMW | O2 Sensor Heater Circuit |
| FIAT | Oxygen Sensor Heater Control, |
| FORD | Heated O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1) |
| HONDA | Primary Heated Oxygen Sensor (Primary HO2S) (Sensor 1) Heater Circuit Malfunction |
| MITSUBISHI | O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1); Oxygen sensor(front) heater |
| NISSAN | O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1) |
| VOLKSWAGEN | HO2S Heater Performance Bank 1 Sensor 1 |
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