All codes › P0135
P0135: O2 Sensor Heater Circuit (Bank 1 Sensor 1)
What it means
The heater inside the bank 1 upstream O2 sensor has failed or its circuit is broken.
Severity: Low Very common; affects emissions only.
Common causes
- Burned-out sensor heater (most common)
- Blown heater fuse
- Damaged wiring
- Connector melted
Most common causes first. Exact causes vary by make, model and engine.
Can I fix it myself?
Often DIY. Check the fuse, then replace the bank 1 upstream sensor.
Repair cost
SEEDED ESTIMATE Roughly $70–$330
Most likely repair: oxygen sensor. Diagnosis fees, taxes and other causes are not included.
| Line | Low | High | Basis |
|---|---|---|---|
| Oxygen sensor | $36 | $168 | Typical listed retail range, source |
| Labor 0.3–1 hr | $30 | $160 | $100–$160/hr, shop survey |
⚠️ This is an editorial placeholder range for this type of repair. It is not based on real invoices or licensed pricing data yet. Real ranges will appear here once enough reader invoices for P0135 are verified.
Verified reader invoices for P0135: 0. Share your repair bill to help build real costs.
Tools that can read P0135
- ScanFixAI: Pro $29.99/mo or $249.99/yr
- OBDAI: Annual PRO bundle $299
- BlueDriver Pro Next-Gen: $119.95 list ($99.95 sale seen)
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