From a shade tree amateur, checking the codes sounds complicated but it’s easier than baking a cake once you plan a step by step process. Print out the instructions or copy it to a word processor and highlight the steps after you determine which of the two ignition/fuel injection system you have. I really don’t think you can break anything. The two black OBD boxes with removable caps are located on the left side fender wall slightly behind the power steering fluid reservoir. The OBD boxes are labeled A and B under the caps. If you think you made a mistake in pushing the button just repeat the process.

Herein lays (or lies) the problem. There are sometimes errors in the codes that are given. I (meaning me) would get the code(s), clear them and wait for the car to reproduce the codes again. Post back with the results.

BTW, few mechanics wouldn’t be dumfounded by the information in the FAQ and the amateur and professional experience on this board.
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Tom F. Couple of Volvos Mods, RainX & cup holders.