P0135 (generic)
O2 Sensor Heater Circuit (Bank 1, Sensor 1)
System: Powertrain · Fuel & Air Metering
Severity: minor · Inspection: often fails
Description
Internal heater in the O2 sensor has failed. Replace the sensor; also check the heater fuse.
Diagnostic snapshot P0135
- Difficulty
- 6/10 — Intermediate diagnostics
- Est. repair cost
- $120 – $450 (parts + typical shop labor)
Diagnostic workflow
- Confirm P0135 with a live scan — note pending vs stored and freeze frame data.
- Inspect wiring/connectors and related sensors before replacing modules.
- Clear codes and road-test; re-scan after two drive cycles if the monitor must set.
Topics
- OBD-II and scan tools (guide)
- Powertrain DTCs (P-prefix) (system)
Related symptoms
None linked yet.
Common fixes (curated)
None linked yet.
Related articles
- Oxygen sensor replacement for check engine light 2016 Toyota Rav4
- DIY Oxygen Sensor Replacement for Check Engine Light 1996 Ford L8000
- 1998 Toyota T100 Oxygen Sensor Replacement for Check Engine Light
- P0135 1996 Ford Ranger: O2 Sensor Heater Circuit Diagnosis
- P0135 1996 Ford Taurus: O2 Sensor Heater Circuit Diagnosis
- P0135 1996 Ford Thunderbird: O2 Sensor Heater Circuit Fix
- P0135 1996 Ford Windstar: O2 Sensor Heater Circuit Diagnosis
- P0135 2001 Toyota 4Runner: O2 Sensor Heater Circuit Diagnosis
- P0135 2002 Toyota 4Runner: O2 Sensor Heater Circuit Fix
- P0135 2000 Toyota Avalon: O2 Sensor Heater Circuit Fix
- P0135 2001 Toyota Avalon: O2 Sensor Heater Circuit Diagnosis
- P0135 2002 Toyota Avalon: O2 Sensor Heater Circuit Diagnosis
Diagnostic bundle (JSON)
Machine-readable graph: related codes, symptoms, fixes, topics, articles, and curated sources rows. Append &external=1 for optional YouTube / Google CSE hits when API keys are configured (see web/.env.example).