P00F3
Humidity Sensor Circuit Range/Performance.
- Generic
- Powertrain
- Generic code
- Low severity
How this code is built
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- 0
- AreaFuel and air metering, auxiliary emission controls
- F3
- FaultThe specific fault in that area
What it means
P00F3 is a generic code meaning the humidity sensor circuit range or performance is out of expectation. The engine control unit compared the humidity reading with other data, such as intake air temperature, ambient temperature or the sensor's own plausible range, and found it implausible, stuck or too slow to respond. The sensor's location and how the reading is used vary by model and engine.
Symptoms
- Engine warning light on
- Slightly rough running or hesitation in some conditions
- Poor fuel economy
- Occasional pinging or reduced performance as the control unit uses fallback values
- No noticeable symptoms other than the warning light
Possible causes
- Faulty or contaminated humidity sensor (stuck or drifting reading)likely
- Damaged wiring, corroded or loose connector at the sensorlikely
- Water, oil or dirt contamination of the sensor or its housingpossible
- Faulty intake air temperature or ambient temperature sensor causing an implausibility with the humidity readingpossible
- Air leak or intake fault affecting the sensor's readings, where the sensor is combined with other intake sensorspossible
- Fault in the engine control unit or outdated calibration, where a known manufacturer bulletin existsrare
How to diagnose
- Read all stored and pending codes and record the freeze frame data, noting ambient conditions and engine temperature when the fault set.
- Check for related codes for intake air temperature, ambient temperature, mass airflow or boost pressure sensors, and deal with those first.
- Locate the humidity sensor using the model's workshop information, as its position and type vary, then inspect the sensor, connector and wiring for damage, corrosion, moisture or chafing.
- Inspect the sensor and its housing for oil, dirt or water contamination and check the intake path for leaks or oil carry-over.
- With a scan tool, view live humidity and intake air temperature values on a cold engine and compare them with the actual conditions and with each other.
- Check the sensor's supply voltage, earth and signal wiring against the manufacturer's wiring diagram for open circuits, short circuits or high resistance.
- Clear the code, road test, and recheck that the reading changes plausibly as the engine warms up.
- Check for any manufacturer software updates or technical bulletins relating to this code for the specific model.
How to fix
- Repair or replace damaged wiring and clean or replace corroded connector terminals.
- Replace the humidity sensor if its readings are stuck, drifting or out of range.
- Clean contamination from the sensor housing where the manufacturer permits, and fix the source of oil or water ingress.
- Repair any faulty intake air or ambient temperature sensor that is causing the implausible reading.
- Repair any intake air leaks found.
- Apply a manufacturer calibration update only if an outdated or faulty calibration is a documented cause for the vehicle.
Can I keep driving?
Low severity
The car can normally be driven as the control unit uses default values, but book it in soon. If the car runs badly, hesitates or goes into limp mode, have it checked sooner.
Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.