[Saudade]

If your MIL is lit, you need to pull the codes first. The connector in just under the dash near the steering column. You need a code reader. If you don't have access to one, typically your local autoparts store will read codes for you. MAKE SURE YOU WRITE DOWN THE EXACT CODES! (Yes I'm shouting). The codes may or may not pinpoint the exact problem but will point you in the right direction.

If your self-test refers to the key-click method, forget it. It's not a reliable method on your model year.