Your 1993 Honda Accord comes equipped with a first generation On-Board Diagnostic (OBD I) system. This diagnostic configuration allows monitored systems in your Accord to send a specific trouble code to the Engine Control Module (ECM) or vehicle computer whenever one of their circuits has detected a function out of the ordinary. In turn, the computer will switch the Check Engine light on to inform you of the problem. Without using special tools, you can access the ECM's memory to help you diagnose and repair these faults with your Honda.
Park your Honda in your driveway or in a safe place away from traffic flow and turn off the ignition switch.
Walk around your vehicle, open the passenger's door and look for a small, two-wire electrical connector hanging loose under the glove box behind the kick panel or under the dashboard on the driver's side, depending on your particular model.
Jump the two wires at the connector with a small paper clip.
Sit behind the steering wheel with a small notepad and pencil.
Turn on the ignition switch but do not start the engine. Watch the dashboard for a blinking Check Engine light. This blink will represent the trouble codes store in your Accord's computer memory, if there are any.
Write down the number of blinks. Long blinks represents the first of a two-digit number, followed by a pause and one or more short blinks that represent the second digit of the two-digit number. For example, if the Check Engine light provides two long blinks, a pause, and three short blinks, the computer is giving you trouble code number 23. If there are more codes, there will be a longer pause, followed by the next trouble code number. Once the computer has given you all the trouble codes in memory, it will provide a longer pause and repeat the same sequence of numbers so that you have a chance to confirm the codes.
Turn off the ignition switch and remove the paper clip from the two-wire electrical connector.
Look up the code numbers in the service manual for your particular Honda Accord model. Also, you can call your local auto parts store or dealer and ask for the definition of the trouble code.
Check the particular system indicated by the trouble code or codes retrieved from your Accord's computer. Keep in mind that a trouble code leading you to an oxygen sensor, for example, only means the circuit or system in which that sensor is located, has triggered a fault. So you need to check the sensor and then wires and connectors, if necessary, to find the fault. Sometimes, a fault in a particular system may cause a sensor in another system to trigger a trouble code.
Repair the system(s) that cause the trouble codes and erase the trouble codes from the computer memory. Disconnect the ground (black) battery cable with a wrench and wait for 30 seconds. Reconnect the ground (black) battery cable with the wrench. The trouble codes have now been erased.
