Emissions

P00F6 — Intake Air Humidity Sensor Circuit Intermittent/Erratic

Severity: low Safe to drive

What P00F6 means

The engine control module is receiving a signal from the intake air humidity sensor that drops out or jumps around in a way that doesn't match real conditions. The sensor measures moisture in the intake air, and the module uses it to fine-tune fueling, ignition timing and emissions control. When the signal is unreliable, it stores P00F6 and turns on the check engine light.

Symptoms

  • Check engine light on
  • Humidity readings on a scan tool that are unrealistic or jumping
  • Rarely, a rough idle
  • Rarely, fuel trim irregularities

Possible causes

  1. Failed intake air humidity sensor
  2. Open, shorted or corroded wiring in the sensor harness
  3. Poor connection at the sensor connector
  4. Dirt or moisture contaminating the sensor or connector
  5. PCM fault or outdated software (unlikely)

How to diagnose

  1. Read all codes and freeze frame data, and look for other intake-related codes
  2. Watch the humidity value in live data and confirm it is erratic
  3. Inspect the sensor connector for corrosion, moisture, loose pins or a damaged lock
  4. Wiggle the harness with the engine running while watching the reading
  5. Test power, ground and signal wires with a multimeter per the factory wiring diagram
  6. Check the wiring for opens and shorts to ground or voltage
  7. Swap in a known-good sensor to confirm the fault
  8. Check for a PCM software update for your model

Common fixes

  • Replace the intake air humidity sensor
  • Repair damaged wiring and clean or replace the connector
  • Update or reflash the PCM if the manufacturer offers it
  • Clear the code and road test to confirm it doesn't return

Questions and answers

Can I drive with a P00F6 code?

Usually yes. The engine keeps running and the PCM uses an estimated value. Have it diagnosed soon to rule out wiring problems that could get worse.

What most often causes P00F6?

Most often it's a poor connection at the connector, damaged wiring or the sensor itself. Start with the connector and harness, then test the sensor.

Why does the code come and go?

The code points to an intermittent signal. Vibration, moisture or temperature changes can break the connection briefly, so the fault doesn't show all the time.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.