Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble with a part that helps the car know how clean the air is coming out of the engine. It's like a sensor that sometimes works and sometimes doesn't.
The O2 sensor heater circuit helps the oxygen sensor reach its operating temperature quickly. An intermittent signal suggests that the circuit is not consistently working as it should.
The P1155 code indicates an issue with the heater circuit of the oxygen sensor located in Bank 2, Sensor 2. The heater is responsible for bringing the sensor up to the optimal temperature for accurate readings. An intermittent signal may be caused by wiring issues, a faulty sensor, or a failing heater element.
• Check Engine Light on
• Poor fuel economy
• Failed emissions test
• Faulty oxygen sensor
• Damaged wiring or connectors
• Blown fuse for the O2 sensor heater circuit
OBD-II: On-Board Diagnostics, a standardized system for diagnosing vehicle issues.
O2 Sensor: Oxygen sensor, measures the amount of oxygen in the exhaust gases.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the oxygen sensor heater circuit for continuity.
• Replace the faulty oxygen sensor.
• Repair or replace damaged wiring or connectors.
• Replace a blown fuse in the heater circuit.
• OBD-II scanner
• Multimeter
• Socket set
$150 - $300
Moderate
• Toyota Camry
• Lexus RX300
• Honda Accord
• Regular maintenance checks
• Ensure proper connections and wiring
• Use quality fuel to reduce sensor wear
Sensor Issue
• Have the vehicle inspected by a professional.
• Avoid ignoring the Check Engine Light.
Check with vehicle manufacturer for warranty coverage on emissions-related components.
This code has been commonly reported in vehicles with aging oxygen sensors or those with wiring issues.
Moderate – Should be addressed soon to avoid further emissions issues.
Driving with a faulty oxygen sensor may lead to increased emissions and could fail an emissions test.
• Engine at operating temperature
• Vehicle running in closed loop mode
Bank 2 Sensor 2 is typically located downstream of the catalytic converter on the side of the engine opposite cylinder 1.
Q: Can I drive with a P1155 code?
A: While the vehicle may still run, it's not recommended as it can lead to poor fuel economy and emissions issues.
Q: How can I prevent this code from appearing?
A: Regular maintenance and ensuring good quality fuel can help prevent issues with the oxygen sensor.
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A wired color-screen reader with readiness hotkeys, live data, code definitions, and data logging.
Good for emissions-related codes because it exposes readiness monitors and live powertrain data.
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Specialty · Smoke machine
Helpful for finding EVAP and vacuum leaks that are hard to see with visual inspection alone.
Helpful for tracking down EVAP and vacuum leaks that can trigger emissions faults.
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Specialty · O2 sensor socket
Helpful when the code points toward exhaust or oxygen-sensor work and space is tight.
Useful when the diagnosis points toward oxygen-sensor removal or replacement.
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Fitment Required · Vehicle-fitment part
Relevant when the code or supporting diagnostics point toward upstream or downstream oxygen-sensor faults.
This code family often involves upstream or downstream oxygen-sensor diagnosis.
Verify exact sensor position and vehicle fitment before buying.
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Fitment Required · Vehicle-fitment part
Relevant when catalyst-efficiency or emissions faults persist after proper diagnosis.
Catalyst-efficiency faults sometimes point toward converter problems after proper testing.
Catalytic converters are highly vehicle-specific and should not be purchased by code alone.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.