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All Toyota fault codes

Oxygen (lambda) sensors

P1135 Air/fuel ratio sensor heater: circuit fault (bank 1, sensor 1)

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P1135 means: Air/fuel ratio sensor heater: circuit fault (bank 1, sensor 1). 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.

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.

This is a make-specific code (Toyota). The exact meaning can vary by model and year.

What you may notice

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

What could be wrong

  1. 1Sensor heater element burnt out · Sensor replacement €80–160
  2. 2Oxygen sensor heater fuse blown · Oxygen sensor replacement €90–180
  3. 3Wire or connector melted or broken · Wiring or connector repair €45–90
  4. 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

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

Standard SAE description: A/F Sensor Heater Circuit (Bank 1 Sensor 1)

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 P1135 mean?

Air/fuel ratio sensor heater: circuit fault (bank 1, sensor 1). 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.

Can I drive with code P1135?

OK to drive, but have it checked soon.

How much does it cost to fix P1135?

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 P1135 fixed?

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

Related codes

P1155Air/fuel ratio sensor heater: circuit fault (bank 2, sensor 1)P1136Fuel trim too lean, additive (bank 1)P1134Oxygen sensor transition time ratio wrong (bank 1, sensor 1)P2243Oxygen sensor: open circuit (reference voltage, bank 1, sensor 1)P2244Oxygen sensor: reading or operation not right (reference voltage, bank 1, sensor 1)P2245Oxygen sensor: signal or voltage too low (reference voltage, bank 1, sensor 1)

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.

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