ACT MAINT DISCREPANCY DISCOVERED BY PIC ON SECOND LEG OF FLT.

Narrative

OUR TRIP STARTED IN SPOKANE; WA (GEG). THE PLANE WE WERE TO USE HAD A MAINT WRITE UP. THE ELECTRIC TRIM SWITCH ON THE CAPT'S SIDE WAS WORKING INTERMITTENTLY. THEY REPLACED THE CAPT'S TRIM SWITCH; SIGNED OFF THE REPAIR 'OPS CHKS GOOD.' THE FIRST THING I DID WHEN I GOT IN THE ACFT WAS TURN ON THE BATTERIES AND PUSH ON THE TRIM SWITCH; I HEARD THE NORMAL BEEP TONES; THE ACTUAL TRIM MOTOR MOVING; AND NOTICED THE TRIM INDICATOR NEEDLE MOVING. I PUSHED THE TRIM SWITCH THE OPPOSITE WAY AND NOTICED PREFLT DUTIES. WE DID ALL NORMAL CHKLISTS AND THE FO FLEW THE FIRST LEG FROM GEG TO FCA (KALISPELL; MT). WE THEN DEPARTED FROM FCA; I FLEW THIS LEG. ON TKOF AFTER THE GEAR WAS UP I STARTED TO TRIM THE ACFT AND NOTICED THAT I WAS GETTING REVERSE MOVEMENT OF THE STABILIZER. I QUICKLY DETERMINED THAT THE CAPT'S TRIM SWITCH WAS OPERATING BACKWARDS. I DIRECTED THE FO TO FLY THE ACFT FROM THAT POINT ON. WE CONTINUED TO BTM (BUTTE; MT) NORMALLY; WITHOUT ANY OTHER PROBS. THE PLANE WAS WRITTEN UP IN BTM AND MAINT WAS CALLED. IN HINDSIGHT I SHOULD HAVE ALSO CHKED THE DIRECTION OF MOVEMENT IN THE BEGINNING. NO TRIM CHK WAS ACTUALLY REQUIRED OF THE CREW; BY ANY CHKLIST OR PROC. SUPPLEMENTAL INFO FROM ACN 298011: IT WAS LATER DISCOVERED THAT THE TRIM SWITCH HAD BEEN WIRED BACKWARDS.