The OBD1 diagnostic port on most Honda models from the late 1980s to mid-1990s is located in the engine bay, on the passenger side near the firewall, usually behind a small plastic cover. Some models place the port inside the cabin, under the dash or behind a trim panel, so check both areas if you don’t see it right away.
OBD1 builds vary by year and model, so the exact location can differ. The port is not standardized like later OBD2 setups, and Honda used several connector styles. If you can’t locate the port in the engine bay, consult the service manual for your exact model-year or search model-specific guides from Honda forums.
Common engine-bay locations
In most Honda OBD1 applications, the port sits in the engine compartment rather than inside the car. Look for a small rectangular connector with a protective cap or a labeled cover near the firewall, the brake booster, or the passenger-side fender area.
- Passenger-side engine bay near the firewall, often just behind the headlight area or near the brake master cylinder. This is the most typical spot on Civics from the late 1980s and early 1990s.
- Inside a small rubber or plastic housing attached to the firewall, sometimes underneath a removable cover near the fender.
- Under or behind a fuse/relay box in the engine bay; the port may be tucked away behind other components.
Because OBD1 configurations varied by model and year, you may need to move a cover or rotate a small panel to reveal the port. If you still can’t locate it, consult your owner's manual or a service manual for your exact model and year.
Model-specific notes (highlights)
Below are general notes about typical placements for popular Honda lines from the OBD1 era. Variation exists among years and trims, so use this as a guide rather than a guarantee.
- Honda Civic (late 1980s to early 1990s): OBD1 port most often sits in the engine bay on the passenger side near the firewall, behind a small plastic cover. Some models place it near the intake or radiator support.
- Honda Accord (late 1980s to early 1990s): Port commonly found in the engine bay, passenger side, behind a protective cover near the firewall; if not visible, check near the brake booster or inner fender shield.
- Honda Prelude and other models from the era: OBD1 port is typically in the engine bay, often on the passenger side near the firewall or ECU, sometimes behind a removable cover in the same vicinity as Civics and Accords.
If you need exact coordinates for a specific model-year, share the exact model and year and we can point to the precise location and provide a photo reference from a reputable service manual or owner community.
How to verify the port location
To confirm you’ve found the right connector, look for a rectangular plug with a set of pins and a protective cap labeled for diagnostics. Compare what you see with the diagrams in your model’s service manual, or check model-specific guides from Honda forums and repair sites. If you’re unsure, a quick photo search for your exact model-year can help confirm the spot.
In summary, while the OBD1 port on most Honda cars from the late 1980s through the mid-1990s is usually in the engine bay on the passenger side near the firewall, there are exceptions. Always verify with model-specific manuals or trusted community knowledge for your exact vehicle.
Summary
The typical OBD1 connector on Honda vehicles from the OBD1 era sits in the engine bay on the passenger side near the firewall, often behind a small cover. If not found there, inspect under dash panels or near the fuse/relay box. Always check your specific model-year manual or trusted Honda repair resources to locate the port accurately.
How to check OBD1 Honda code?
So for example long blink short blink is 11. And uh long blink long blink is 20 there's something like 60 codes it could be more or less i'm just I'm just guessing.
How to identify Honda OBD1 ECU?
- All Honda ECU's have an ECU part number which is located on the side of the ECU which allows for easy identification. The middle three characters are the most useful to identify what type of ECU it is. Different generation ECUs may use the same characters. e.g. a P75 OBD I ECU is different from a P75 OBD II ECU.
What is OBD1 and OBD2 honda?
OBD stands for On-board diagnostics. The two main types of diagnostic systems in vehicles is OBD1 and OBD2. OBD1 was used in vehicles up to as late as 2006 and anything newer will be OBD2.
Where is the OBD1 connector located?
Light see how it's blinking. In a pattern. One one two that means 12 so that's just the check code it does that three times before it gives you the real.