Since you can’t use an OBD-II (on-board diagnostic) tool to hook into an OBD port in order to find the trouble codes for a ‘93 Accord, you’re going to have to decipher your uncle’s trouble codes the old-fashioned way. So grab a paper clip, a pen, and some paper, and let’s do this!
If doing this is far too much of a headache for you and your uncle, take his Accord to a Honda dealership, where technicians will do the work of diagnosing and fixing any issues for you.