P00F6
Humidity Sensor Circuit Intermittent/Erratic.
- 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
- F6
- FaultThe specific fault in that area
What it means
P00F6 means the engine control unit has seen an intermittent or erratic signal from the humidity sensor circuit. The humidity reading jumped, dropped out or changed in a way that does not match real conditions or the other intake sensors. Where the sensor is fitted and how the reading is used (such as fuel, ignition or EGR corrections) depends on the make and engine.
Symptoms
- Engine warning light on
- Slightly rough running or hesitation at times
- Poorer fuel economy
- Occasional hesitation under load
- Other intake or air temperature codes stored alongside it
- No noticeable symptoms in many cases
Possible causes
- Loose, corroded or damaged connector at the humidity sensorlikely
- Chafed, broken or high-resistance wiring between the sensor and the control unit (signal, supply or earth)likely
- Faulty humidity sensor giving an unstable outputlikely
- Water, oil or contamination in the sensor or connectorpossible
- Poor earth or unstable supply voltage to the sensorpossible
- Fault inside the engine control unitrare
- Outdated control unit software, only where the manufacturer lists it as a known causerare
How to diagnose
- Read all stored codes and freeze frame data, noting engine temperature, load and whether the fault was set at a particular time or in wet weather
- Check for any manufacturer bulletins or known issues for this model and engine
- Visually inspect the sensor, its connector and the wiring for damage, moisture, corrosion, chafing or bent pins
- Wiggle-test the wiring and connector with the engine running while watching the live humidity reading for dropouts or jumps
- Compare the live humidity value with intake air temperature and ambient conditions to see whether it is plausible
- Check the sensor supply voltage and earth against the manufacturer's specification
- Test the signal wire for continuity, short to earth or short to supply, with the control unit and sensor disconnected
- Clear the code and road test to see if it returns, then recheck the live data
How to fix
- Clean, repair or replace the damaged connector terminals
- Repair or replace the damaged wiring section
- Replace the humidity sensor if its output is unstable and the wiring checks out
- Remove the source of water or oil contamination and replace any affected parts
- Repair the supply or earth fault
- Update or reprogram the control unit only if the manufacturer lists outdated software as the cause, or replace the unit if it is proven faulty
Can I keep driving?
Low severity
The car can normally be driven while you book it in for diagnosis. If it starts running poorly or other warning lights appear, have it checked sooner.
Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.