What does code P0135 mean and is it safe to drive?
P0135: O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1). Here’s what it means, what usually causes it, what repairs typically cost, and how urgent it is to keep driving.
PowertrainGenerally safe to drive
Repair cost
$80–$300
System
Powertrain
Urgency
low
What this code means
The heater circuit for the upstream O2 sensor on bank 1 has a fault. Sensor may still work but take longer to go closed-loop.
Common causes
- Failed O2 sensor (heater element)
- Open or short in heater wiring
Symptoms
- Check Engine Light
- Possible slightly worse fuel economy
Typical fixes
- Replace bank 1 sensor 1 O2 sensor
- Repair wiring
Repair cost range
Repairs for P0135 often fall between $80 and $300, depending on the cause and your vehicle.