Understanding your 2010 Ford Focus’s fuse box is crucial for diagnosing and resolving electrical issues, especially when it comes to your OBD2 port. This guide provides a comprehensive overview of the fuse locations in your 2010 Ford Focus, focusing on fuses relevant to the OBD2 system, and how to troubleshoot potential problems.
Locating the Fuse Boxes in Your 2010 Ford Focus
Your 2010 Ford Focus has two main fuse boxes: one located inside the passenger compartment and another in the engine compartment. Knowing where these are is the first step in addressing any electrical malfunction, including issues with your OBD2 port.
Passenger Compartment Fuse Box
The passenger compartment fuse box is positioned for easy access from inside your vehicle.
To find it:
- Look beneath the steering wheel, on the left-hand side, near the brake pedal.
- You may need to remove a protective cover located under the steering wheel to fully expose the fuse box panel.
This fuse box controls many of the interior electrical functions of your Ford Focus.
Engine Compartment Fuse Box
The second fuse box is located in the engine compartment, housing fuses that manage critical engine and vehicle systems.
To access it:
- Open the hood of your 2010 Ford Focus.
- The power distribution box, which houses the engine compartment fuses, is situated within the engine bay. Refer to your vehicle’s owner manual for the precise location, as it can slightly vary.
This box is responsible for high-power fuses and relays vital for the engine and related systems.
2010 Ford Focus Fuse Diagrams and OBD2 Relevance
Below are the fuse diagrams for both the passenger and engine compartments of your 2010 Ford Focus. These diagrams detail the location and function of each fuse. While “OBD2 fuse” isn’t explicitly labeled, the Data Link Connector (DLC), which is another name for the OBD2 port, is protected by a fuse. Let’s examine the diagrams to pinpoint this crucial fuse.
Passenger Compartment Fuse Diagram (2010 Ford Focus)
| № | Amp Rating | Protected circuits |
|---|---|---|
| 1 | 30A | Not used (spare) |
| 2 | 15A | Brake switch (high-mount brake lamp) |
| 3 | 15A | Not used (spare) |
| 4 | 30A | Not used (spare) |
| 5 | 10A | Shift interlock |
| 6 | 20A | Right front turn lamp/Left front turn lamp, Rear stop/turn lamps |
| 7 | 10A | Left low beam headlamp |
| 8 | 10A | Right low beam headlamp |
| 9 | 15A | Interior lamps |
| 10 | 15A | Instrument panel backlighting |
| 11 | 10A | Not used (spare) |
| 12 | 7.5A | Power mirrors |
| 13 | 5A | SYNC® |
| 14 | 10A | Not used (spare) |
| 15 | 10A | Recirculated air, Air conditioning |
| 16 | 15A | Not used (spare) |
| 17 | 20A | Power locks, Trunk release |
| 18 | 20A | Heated seats |
| 19 | 25A | Not used (spare) |
| 20 | 15A | Data link connector |
| 21 | 15A | Fog lamps, Fog lamp indicator |
| 22 | 15A | Parking lamps |
| 23 | 15A | High beam lamps |
| 24 | 20A | Horn |
| 25 | 10A | Demand lamps, Trunk lamps |
| 26 | 10A | Instrument cluster |
| 27 | 20A | Ignition switch |
| 28 | 5A | Radio (Start) |
| 29 | 5A | Instrument cluster (Run/Start) |
| 30 | 5A | Not used (spare) |
| 31 | 10A | Not used (spare) |
| 32 | 10A | Restraints control module |
| 33 | 10A | Not used (spare) |
| 34 | 5A | Not used (spare) |
| 35 | 10A | Anti-lock brake system (ABS) |
| 36 | 5A | Passive anti-theft system (PATS) module |
| 37 | 10A | Climate control (Run/Start) |
| 38 | 20A | Subwoofer |
| 39 | 20A | Radio, Center information display, Electronic finish panel |
| 40 | 20A | Not used (spare) |
| 41 | 15A | Door lock/sunroof switch illumination, Auto dimming rear view mirror, Ambient lighting |
| 42 | 10A | Not used (spare) |
| 43 | 10A | Not used (spare) |
| 44 | 10A | Not used (spare) |
| 45 | 5A | Front wipers (logic) |
| 46 | 7.5A | Front passenger sensing system |
| 47 | 30A (circuit breaker) | Sunroof, Power windows |
| 48 | — | Delayed accessory relay |
Fuse #20 (15A) in the passenger compartment fuse box is designated for the Data Link Connector. This is the fuse you need to check if you are experiencing issues with your OBD2 port in your 2010 Ford Focus.
Engine Compartment Fuse Diagram (2010 Ford Focus)
| № | Amp Rating | Protected circuits |
|---|---|---|
| 1 | 15A | Heated mirror |
| 2 | 30A | Rear defrost |
| 3 | 20A | Power point |
| 4 | 20A | Fuel pump |
| 5 | 10A | Powertrain control module (PCM) keep alive power, Canister Vent |
| 6 | 15A | Alt sense |
| 7 | 10A | Reverse lamps |
| 8 | — | Not used |
| 9 | 40A | Anti-lock brake system (ABS) motor |
| 10 | 30A | Wipers |
| 11 | 30A | Starter |
| 12 | 40A | Blower |
| 13 | 10A | A/C clutch |
| 14 | 10A | PCM relay coil |
| 15 | 20A | Power point |
| 16 | 20A | Cooling fan—low |
| 17 | 30A | Cooling fan—high |
| 18 | 20A | ABS solenoid |
| 19 | — | Not used |
| 20 | — | A/C clutch relay |
| 21A | Rear defrost relay | |
| 21B | — | Not used |
| 21C | Blower relay | |
| 21D | PCM relay | |
| 22 | 10A | Fuel injector |
| 23 | — | Not used |
| 24 | — | Not used |
| 25 | — | Not used |
| 26 | 15A | PCM – emission related powertrain components |
| 27 | — | Not used |
| 28 | 15A | PCM |
| 29 | 15A | Ignition |
| 30A | — | Cooling fan low speed relay |
| 30B | — | Starter relay |
| 30C | — | Not used |
| 30D | — | Cooling fan high speed relay |
| 31A | — | Reverse lamp relay |
| 31B | — | Fuel pump relay |
| 31C | — | Wiper power relay |
| 31D | — | Not used |
| 31E | — | Not used |
| 31F | — | Not used |
| 32 | — | A/C clutch diode |
| 33 | — | EEC diode |
| 34 | — | One touch integrated start (OTIS) diode |
| 35 | 10A | Run/Start |
While the engine compartment fuse box diagram doesn’t directly list an “OBD2 fuse,” it’s important to be aware of its location as it houses fuses for critical systems that might indirectly affect OBD2 functionality, such as the Powertrain Control Module (PCM) fuses (#5, #26, #28).
Troubleshooting OBD2 Port Fuse Issues
If your OBD2 scanner is not powering on or connecting to your 2010 Ford Focus, the first and easiest step is to check the Data Link Connector fuse, which we identified as Fuse #20 (15A) in the passenger compartment fuse box.
Steps to Check and Replace a Fuse:
- Locate the Passenger Compartment Fuse Box: As described earlier, it’s under the steering wheel.
- Identify Fuse #20: Use the fuse diagram provided or the diagram inside the fuse box cover to locate fuse #20.
- Inspect the Fuse: Carefully pull out the fuse. You can usually do this by hand or use a fuse puller tool (often found in the fuse box itself or engine compartment fuse box). Hold the fuse up to the light and check if the thin wire inside is broken or melted. If it is, the fuse is blown.
- Replace the Fuse (if blown):
- Ensure the ignition is turned off.
- Replace the blown fuse with a new fuse of the exact same amp rating (15A). Using a fuse with a higher amperage rating can damage your vehicle’s electrical system.
- Push the new fuse firmly into the fuse slot.
- Test Your OBD2 Port: Try using your OBD2 scanner again to see if it now powers on and connects.
Important Considerations:
- Repeatedly Blown Fuses: If the OBD2 port fuse blows again immediately after replacement, there is likely an underlying issue, such as a short circuit in the OBD2 port wiring or a connected device drawing excessive current. Further diagnosis by a qualified mechanic may be needed.
- Other Potential Issues: If replacing the fuse doesn’t solve the OBD2 port problem, other issues could be at fault, including a faulty OBD2 scanner, wiring problems, or issues with the vehicle’s computer system.
Maintaining Your 2010 Ford Focus Fuse Box
Regularly checking your fuse boxes is not typically needed, but understanding their location and how to check fuses is a valuable part of vehicle ownership. Knowing the 2010 Ford Focus Obd2 Fuse Location empowers you to perform basic troubleshooting and potentially save time and money on simple electrical repairs.
For more in-depth information on fuses and electrical systems, refer to your 2010 Ford Focus owner’s manual and consult with a certified mechanic for complex issues.
Further Resources:
How to check the fuses?
How to replace a blown fuse?
Why do car fuses blow?
Types of automotive fuses
