The most common problem on ABS systems is one of the wheel sensors or circuits. Haven't seen a pattern failure for PTs, but getting the code pulled should point you in the right direction.
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2004 Dark Plum Base with windows tinted, cabin filter, silencers removed, fog lights, 18\'s, all Red taillights, Blaine\'s struts, modesty cover, color-matched center dash, 06 rear bumper
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