P01F5
O2 Sensor Circuit No Activity Detected Bank 1 Sensor 4
Bank 1 sensor 4 O2 sensor shows no signal change despite operating conditions that should produce activity. A drifted or sluggish lambda sensor lets the mixture run lean or rich without correction — fuel economy and emissions suffer immediately.
Bank 1 sensor 4 O2 sensor shows no signal change despite operating conditions that should produce activity. A drifted or sluggish lambda sensor lets the mixture run lean or rich without correction — fuel economy and emissions suffer immediately.
Common causes
- high
Sensor dead or unheated
One of the most commonly reported causes for this code — check this first.
Typical part cost: $90-440
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
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Frequently asked questions
What does P01F5 mean?
P01F5 means "O2 Sensor Circuit No Activity Detected Bank 1 Sensor 4". It is a generic OBD-II code that points to a fault in the fuel & air metering.
What are the most common causes of P01F5?
sensor dead or unheated — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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