P1155

Air/Fuel Sensor Heater Circuit (Bank 2 Sensor 1)

Car Fault Codes Toyota Emissions & exhaust

Can you still drive? Yes, normally

Who can fix it? DIY with some experience

Typical repair time 30 minutes – 2 hours

Typical cost SAR 100 to 900

What it means

This is a Toyota-specific code; the same number may mean a different fault on other makes. It applies to V6 and V8 engines only and means the engine computer detected an open or short in the heater circuit of the Bank 2 upstream air/fuel (A/F) sensor. It does not harm the engine directly but delays precise mixture control after start-up.

Models covered: Toyota models with air/fuel ratio (A/F) sensors, mainly model years around 1998–2004 (e.g. Camry, Corolla, RAV4, Highlander, Sienna, Tacoma, Tundra); later models use generic codes (P2195–P2198, P0031/P0032). Bank 2 exists on V6/V8 engines only.

Symptoms4

Check engine light on.
Slightly higher fuel consumption.
P1135 may appear with it when a fuse shared by both sensors is the cause.
Usually no obvious driveability symptoms.

Possible causes5

Open heater inside the Bank 2 sensor.
Blown fuse feeding the heater, or a failed relay on models that use one.
Sensor wiring melted or rubbing on the exhaust at the back of the engine.
Corroded or loose connector.
Fault in the heater control circuit inside the engine computer (rare).

How to diagnose4

If P1135 and P1155 appear together, start with the shared fuse or relay and the power feed.
If P1155 is alone, unplug the Bank 2 sensor and measure heater resistance against the Toyota specification.
Confirm battery voltage at the heater supply terminal with the ignition on.
Inspect the wiring route on the Bank 2 side for melting or chafing.

How to fix4

Replace the fuse or relay after fixing the cause of the short.
Repair wiring or the connector.
Replace the Bank 2 sensor if its heater is open.
Clear the codes and confirm the code stays away after a cold start.

Repair cost

0–500

500–2,000

2,000–5,000

5,000+

In Saudi riyals; the highlighted part is the expected range for this fault.

A fuse or wire is cheap; replacing the sensor is the top of the range, and labor rises when it sits at the rear of the engine.

Prices are rough estimates for common cars at independent workshops and vary with the car and the source of the part.
Prices last updated: September 2026

Frequently asked questions

What does it mean when P1135 and P1155 appear together?

Both codes together point to a shared cause such as a fuse, relay or power feed, because two heaters failing at the same moment is less likely.

What code do newer models use?

Newer models use the generic Bank 2 heater codes, such as P0051 (circuit low) and P0052 (circuit high).

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This guide is for information only and does not replace an inspection by a qualified technician. If the fault involves brakes, steering, engine temperature, electrics or refrigerant, do not attempt the repair yourself.

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