Try the Brake Light Switch it should be located under the dash where the brake pedal arm attachs and pivots.
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Also check the multifunction switch in the steering column. These are notorious for shorting out in the sunfires/cavaliers. Manufacturer number: ARBC505802, AutoZone part #SW824, shoud cost you about $40 and is easy to replace. Tip: try jiggling the hazard light switch on the steering column and see if you get any activity in the brake lights.