Source-backed diagnostic reference
P0135 EV diagnostic code
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
Reference status: This page preserves source-backed code definitions for discovery. Manufacturer/model applicability, repair steps and safety conclusions are not treated as verified unless a manufacturer-specific verified report is available.
Reference definitions
- 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 Source
- GENERIC: O2 Sensor Heater Circuit Bank 1 Sensor 1 Source
- GENERIC: O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1) Source
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