thats the input for your vibe's computer. u can use that to check the codes for ur check engine light, or to modify ur computer. and maybe something else that idk :/
04 Pontiac Vibe Gray, M+T package Custom Front Bumper Paint5% window tint everywhere except three front windows 12" Pioneer IMPP subPro bend bandpass boxBoss 1600w 4Ch amp6, 6.5 Infinity Kappa 62.9i 450w each
that is your OBII plug as already mentioned it used by mechanics to connect to your car's brain/ecu. So to answer your question, no nothing needs to be plug in to it.If you buy a scanguage, it would plug in there.
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