The 39-year-old actor was pulled over for a routine traffic stop at around 2 AM -- when cops allegedly smelled alcohol on his breath.
We're told Chavira was given field sobriety tests at the scene -- but they didn't go so well -- so cops arrested him on suspicion of DUI. Sources say Chavira refused to take a blood or breath test.
Chavira was taken to a nearby jail -- where he was booked. He's currently being held on $25,000 bail.
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