Engine Error
P0135
O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
Severity
Medium
Symptoms
Poor fuel economy, check engine light
Common Causes
- Internal O2 sensor heater failure
- Blown fuse
- Faulty wiring or connector
- PCM failure
How to Fix
- 1 Check O2 heater fuse
- 2 Test heater circuit resistance
- 3 Replace upstream O2 sensor
- 4 Inspect wiring harness
Estimated Repair Cost
USD
$150
–
$350
O2 sensor: $100 - $250; Labor: $50 - $100