Oxygen (lambda) sensors

P0055 Oxygen sensor heater: resistance wrong (bank 1, sensor 3)

By: Diagno editorial team · Updated: 2026-10-15

P0055 means: Oxygen sensor heater: resistance wrong (bank 1, sensor 3). The oxygen sensor has a heater so it warms up quickly. OK to drive, but have it checked soon. The most common repair costs about €80–160 in Estonia, depending on make and model. The most common cause: sensor heater element burnt out.

Is it safe to drive?OK to driveOK to drive, but have it checked soon.

Sensor replacement€80–160parts and labour in Estonia, depending on make and model

What it means

The oxygen sensor has a heater so it warms up quickly. If the heater doesn't work, the sensor gives no proper reading on a cold engine and fuel use goes up. Sensor 2 or 3 sits after the catalytic converter.

What you may notice

Engine light on
Slightly higher fuel consumption
Usually no change in how the car drives

What could be wrong

1Sensor heater element burnt out · Sensor replacement €80–160
2Oxygen sensor heater fuse blown · Oxygen sensor replacement €90–180
3Wire or connector melted or broken · Wiring or connector repair €45–90
4Engine computer fault (rare) · Control unit check and software €150–300

Repair difficulty: Easy

What you can check yourself

Check the oxygen sensor heater fuse. Make sure the sensor wire isn't touching the hot exhaust. You can do the simpler checks yourself.

How we fix it

We measure heater resistance and supply
We replace the fuse or repair the wire
We replace the oxygen sensor

Standard SAE description: HO2S Heater Resistance (Bank 1, Sensor 3)

This code usually comes with: Check engine lightSee what the light means →

Want a definite answer?

Bring the car to our workshop in Estonia for diagnostics. We read the fault codes, test the sensors and tell you what is wrong. Repair price depends on the work involved, generally €45 per hour.

Book a diagnostic check

Questions

What does fault code P0055 mean?

Oxygen sensor heater: resistance wrong (bank 1, sensor 3). The oxygen sensor has a heater so it warms up quickly. If the heater doesn't work, the sensor gives no proper reading on a cold engine and fuel use goes up. Sensor 2 or 3 sits after the catalytic converter.

Can I drive with code P0055?

OK to drive, but have it checked soon.

How much does it cost to fix P0055?

It depends on the cause: sensor replacement €80–160; oxygen sensor replacement €90–180; wiring or connector repair €45–90. Prices include labour at €45/h, depending on make and model.

How is P0055 fixed?

We measure heater resistance and supply. We replace the fuse or repair the wire. We replace the oxygen sensor.

Based on AI combined with our hands-on workshop experience and knowledge. This information is general and prices are approximate (Estonian workshop rates). The same code can mean different things on different cars. Only an inspection of the car gives a definite answer.