Understanding your 2005 Honda Accord’s fuse box is crucial for basic car maintenance and troubleshooting electrical issues. One common concern for car owners is the OBD2 port, used for diagnostics and emission checks. If your OBD2 port isn’t working, a blown fuse is a likely culprit. This guide will help you locate the relevant fuses for your 2005 Accord’s OBD2 system and understand how to address fuse-related problems.
Your 2005 Honda Accord actually has two main fuse boxes. Knowing where they are is the first step to checking your OBD2 fuse or any other electrical component.
The first fuse box is located under the hood. This is often referred to as the primary fuse box and it controls many of the car’s essential systems.
2005 Honda Accord under hood fuse box diagramUnder-hood fuse/relay box diagram
The second fuse box is located inside the car, usually under the dashboard on the driver’s side. This interior fuse box manages circuits for interior accessories and some engine management components.
2005 Honda Accord interior fuse box diagramInterior fuse box diagram
While there isn’t a fuse explicitly labeled “OBD2 fuse” in the 2005 Honda Accord fuse diagrams, several fuses are vital for the operation of the OBD2 system. The OBD2 port needs power and a functioning ECU (Engine Control Unit) to communicate diagnostic data. Therefore, fuses related to the ECU, ignition, and backup power are important to check when troubleshooting an OBD2 port issue.
Let’s examine the fuse listings for both fuse boxes to identify potential fuses linked to your OBD2 system:
Under-Hood Fuse Box Diagram Fuse List:
| Type | No. | Description |
|---|---|---|
| Fuse MINI 10A | 1 | Left Headlight Low |
| Fuse MINI 30A | 2 | Rear Defroster Coil |
| Fuse MINI 10A | 3 | Left Headlight Hi |
| Fuse MINI 15A | 4 | Small Light |
| Fuse MINI 10A | 5 | Right Headlight Hi |
| Fuse MINI 10A | 6 | Right Headlight Low |
| Fuse MINI 7.5A | 7 | Back Up |
| Fuse MINI 15A | 8 | FI ECU |
| Fuse MINI 20A | 9 | Condenser fan |
| Fuse MINI 20A | 11 | Cooling Fan |
| Fuse MINI 30A | 11 | Cooling Fan [6-cylinder models] |
| Fuse MINI 7.5A | 12 | MG. Clutch |
| Fuse MINI 20A | 13 | Horn, Stop |
| Fuse FMX/JCase 40A | 14 | Rear Defroster |
| Fuse FMX/JCase 40A | 15 | Back Up, ACC |
| Fuse MINI 15A | 16 | Hazard |
| Fuse FMX/JCase 30A | 17 | ABS Motor |
| Fuse FMX/JCase 30A | 17 | TCS Motor [6-cylinder models] |
| Fuse FMX/JCase 20A | 18 | ABS F/S |
| Fuse FMX/JCase 40A | 18 | TCS [6-cylinder models] |
| Fuse FMX/JCase 40A | 19 | Ignition Coil, DRL [Canada] |
| Fuse FMX/JCase 40A | 20 | Power Seats, Seat Heaters |
| Fuse FMX/JCase 40A | 21 | Heater Motor |
| Multi fuse block MUSB | 22 | Battery |
| Multi fuse block MUSB | 23 | +B IG1 Main // Power Window Main |
In the under-hood fuse box, Fuse #8 (15A, FI ECU) is a critical fuse to check. “FI ECU” stands for Fuel Injection Engine Control Unit. A blown fuse here can directly impact the ECU’s ability to communicate, which is essential for OBD2 functionality. Also, Fuse #7 (7.5A, Back Up) and Fuse #15 (40A, Back Up, ACC) provide backup power and accessory power, which might be relevant for the OBD2 system’s power supply.
Interior Fuse Box Diagram Fuse List:
| Type | No. | Description |
|---|---|---|
| Fuse MINI 15A | 1 | Drive by Wire [6-cylinder models] |
| Fuse MINI 15A | 2 | Ignition Coil |
| Fuse MINI 10A | 3 | Day Light [On Canadian models] |
| Fuse MINI 15A | 4 | Laf Heater |
| Fuse MINI 10A | 5 | Radio |
| Fuse MINI 7.5A | 6 | Interior Light |
| Fuse MINI 10A | 7 | Back-Up Lights |
| Fuse MINI 20A | 8 | Door Lock |
| Fuse MINI 15A | 9 | Front Accessory Sockets |
| Fuse MINI 7.5A | 10 | IG OPDS |
| Fuse MINI 30A | 11 | IG Wiper |
| Fuse MINI 7.5A | 12 | RR FOG |
| Fuse MINI 20A | 13 | Passenger’s Power Seat Recline |
| Fuse MINI 20A | 14 | Driver’s Power Seat Slide |
| Fuse MINI 20A | 15 | Heated Seat |
| Fuse MINI 20A | 16 | Driver’s Power Seat Recline |
| Fuse MINI 15A | 18 | IG ACG |
| Fuse MINI 15A | 19 | IG Fuel Pump |
| Fuse MINI 7.5A | 20 | IG Washer |
| Fuse MINI 7.5A | 21 | IG Meter |
| Fuse MINI 10A | 22 | IG SRS |
| Fuse MINI 7.5A | 23 | IGP (PGM-FI ECU) |
| Fuse MINI 20A | 24 | Left Rear Power Window |
| Fuse MINI 20A | 25 | Right Rear Power Window |
| Fuse MINI 20A | 26 | Right Front Power Window |
| Fuse MINI 20A | 27 | Driver’s Power Window |
| Fuse MINI 20A | 28 | Moonroof |
| Fuse MINI 7.5A | 30 | IG HAC |
| Fuse MINI 7.5A | 32 | ACC |
| Fuse MINI 7.5A | 33 | HAC OP |
| Fuse MINI 20A | 17 | Passenger’s Power Seat Slide |
In the interior fuse box, Fuse #23 (7.5A, IGP (PGM-FI ECU)) is another ECU-related fuse. “PGM-FI ECU” also refers to the Programmed Fuel Injection Engine Control Unit. Checking this fuse is also essential. Additionally, fuses with “IG” (Ignition) in their description, like Fuse #18 (15A, IG ACG), Fuse #19 (15A, IG Fuel Pump), Fuse #21 (7.5A, IG Meter), and Fuse #22 (10A, IG SRS), might indirectly affect the OBD2 system as they are part of the car’s ignition and control systems. Fuse #32 (7.5A, ACC) for Accessory power is also worth checking.
Troubleshooting Steps for your 2005 Accord Obd2 Fuse Issue:
- Locate the Fuse Boxes: Use the diagrams above to find the under-hood and interior fuse boxes in your 2005 Honda Accord.
- Identify Potential Fuses: Refer to the fuse lists and pinpoint the fuses mentioned above: Under-hood Fuse #8, Interior Fuse #23, and other related fuses like Back Up and Ignition fuses.
- Inspect the Fuses: Visually inspect each fuse. A blown fuse typically has a broken wire inside or a darkened/melted appearance. You can also use a fuse tester for more certainty.
- Replace Blown Fuses: If you find a blown fuse, replace it with a fuse of the exact same amperage. Using a fuse with a higher amperage can damage your car’s electrical system.
- Test your OBD2 Port: After replacing any blown fuses, try using your OBD2 scanner again to see if it’s now working.
If you’ve checked all the relevant fuses and your OBD2 port is still not functioning, the problem might be more complex than a simple blown fuse. It could be a wiring issue, a problem with the OBD2 port itself, or a more serious ECU malfunction. In such cases, it’s recommended to consult a qualified mechanic or visit a service professional at cardiagnosticnearme.com for further diagnosis and repair.
