Ford Fusion Quiz
Engine Emission Control

On-Board Diagnostics (OBD-II)

In this manual: Engine Emission Control
Introduction — 7Environment — 1At a Glance — 1Child Safety — 9Seat Belts — 8Personal Safety System™ — 1Additional Restrictions — 8Keys and Remote Controls — 8MyKey™ — 5Doors & Locks — 10Safety — 3Steering Wheel — 5Wipers and Washers — 4Lighting — 8Automatic High Beam Control — 3Windows and Mirrors — 6Instrument Cluster — 4Information Displays — 5Climate Control — 10Seats — 9Garage Door Opener — 1Auxiliary Power Points — 3Storage Compartments — 1Starting and Stopping the Engine — 4Unique Driving Characteristics (if equipped) — 1Fuel and Refueling — 9Engine Emission Control — 5Infection Transmission — 1All-Wheel Drive — 1Brakes — 4Traction Control — 1Stability Control — 1Park Aid — 13Cruise Control — 10Driver Assistance — 14Loading — 1Tow/Haul — 5Driving Tips — 3Roadside Emergencies — 5Customer Assistance — 6Fuses — 3Maintenance — 16Vehicle Care — 9Wheels and Tires — 13Capacities and Specifications — 11Connected Vehicle — 1Wi-Fi Hotspot — 1Audio System — 7SYNC™ — 7SYNC™ 3 — 16Accessories — 1Ford Protect — 3Scheduled Maintenance — 5Appendices — 4
4steps
~24min
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Your vehicle has a computer known as the On-Board Diagnostic (OBD-II) system, which monitors the engine emission control system. The system protects the environment by making sure your vehicle continues to meet government emission standards. The OBD-II system also helps the service technician properly service your vehicle.

Ford Fusion. On-Board Diagnostics (OBD-II)When the Service Engine Soon indicator is on, the OBD-II system has detected a malfunction. Temporary malfunctions may cause the Service Engine Soon indicator to illuminate. Examples:

  1. Your vehicle ran out of fuel - the engine may misfire or run poorly.
  2. Poor fuel quality or water in the fuel - the engine may misfire or run poorly.
  3. The fuel filler cap may not have been closed properly.
  4. Driving through deep water - the electrical system may be wet.

You can correct these temporary malfunctions by filling the fuel tank with good quality fuel, closing the fuel filler cap properly, or allowing the electrical system to dry out. After three driving cycles without these or any other temporary malfunctions present, the Service Engine Soon indicator should turn off on the next engine start. A driving cycle consists of a cold engine start followed by mixed city and highway driving. No additional vehicle service is required.

If the Malfunction Indicator Lamp (MIL) remains illuminated, have the vehicle serviced as soon as possible. Although some faults detected by OBD-II may not have noticeable symptoms, continuing to drive with the Check Engine light illuminated may result in increased emissions, reduced fuel economy, reduced engine and transmission smoothness, and more costly repairs.

Test yourself

A quick Ford Fusion quiz: every answer comes with an explanation and a link to the manual page.