Automobile Onboard Diagnostics systems are designed to identify problem components in vehicles and report them to you through indicators or codes. OBD1, the first generation of these diagnostic systems are often difficult to locate and read the codes.

Things You Will Need

you may need a paperclip and some basic hand tools depending on where your OBD1 connector is located.

Step 1

Once you are sure your car is equiped with an OBD1 system, you will need to identify where your port or service connector is located. Some cars may have them under the hood along the firewall, somewhere under the dash or else where. The fourth generation Honda Accords had OBD1 connectors behind the passenger door kick panel. Using your repair manual or some internet research to determine the location of your connector. Once you have identified the location and have access to it, you are ready to proceed.

Step 2

To get your ehicle to display the OBD1 codes to you you have to connect to the service connector. With OBD1, this is generally done by jumping the wires and reading the flashes on a dashboard indicator. For example, on OBD1 Hondas, you could use a paperclip to jump the two wires in the service connector

Step 3

Once you have successfully jumped the service connector, turn the car ignition to the on position. You do not want to start the car, but just get it to the on position so that the electrical systems are powered. At this time your check engine light will begin to flash. OBD1 codes are represented by a series of long and short flashes; long flashes represent the number 10, short flashes represent the number 1. Add these numbers together to get the code the system is reporting to you. Some vehices will also have a second system to represent Transmission trouble codes. In OBD1 Hondas, the drive indicator "D" will flash in a similar way to represent the trouble codes for the transmisson system.

Step 4

Once you have all of the codes that have been reported to you, you will need to research them. Auto delaerships, auto repair shops, auto parts stores, repair manuals and the internet are all good places to research the meaning and possible solutions to the car problems reported by the diagnostic codes.

With this information you should now be able to read your automobile OBD1 codes. Once you have determined if your car is OBD1 compliant, locate your service connector and jump the connection. Turn your ignition to the on position and record the codes displayed to you on your instrument panel. Some quick research will show you how to find and read your OBD1 codes.

Tips & Warnings

OBD1 cars were generally produced from 1993-1995; however, some automakers may have started or switched to OBD2 at different times due to a variety of reasons.

US Cars were mandated to be OBD2 compliant in 1996

Have a pencil and paper handy to write down your codes when reading them.