B737-500 CREW FOUND THAT THE YOKE TRIM SWITCHES WERE INOP. AFTER MAINT FIXED THEM; THEY BECAME INOP IN THE AIR. THIS WAS A CHRONIC PROB.

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DURING ACFT PREFLT; FOUND THE STABILIZER TRIM SWITCH ON BOTH THE CAPT'S AND THE FO'S YOKE WOULD NOT ACTIVATE STABILIZER TRIM. MAINT WAS CALLED. THIS ACFT HAD JUST COME OUT OF MAINT FOR THE SAME PROB WITH SEVERAL PARTS REPLACED. AFTER AN HR DELAY; REPLACEMENT OF THE STABILIZER ACTUATOR; AND MUCH TESTING; WE WERE RELEASED WITH A CLEAN MAINT RELEASE. ON TKOF FROM RWY 8; I ATTEMPTED TO TRIM THE STABILIZER ON THE CLBOUT; BUT THERE WAS NO MOVEMENT. I HAD THE FO TRY HIS TRIM SWITCH AND HE WAS UNABLE TO TRIM THE STABILIZER EITHER. THE SPD TRIM FEATURE INTERFERED WITH MY ATTEMPTS TO MANUALLY TRIM THE ACFT; SO I DIRECTED BOTH MAIN AND AUTOPLT CUTOUT SWITCHES BE MOVED TO CUTOUT. THE ACFT FLEW FINE WITH MANUAL TRIM. DURING THE CLB AND BEFORE WE HAD AN OPPORTUNITY TO CONTACT DISPATCH; I HAD THE CUTOUT SWITCHES PLACED BACK TO NORMAL TO CHK THE AUTOPLT TRIM FUNCTION. AFTER RESETTING BOTH SWITCHES; THE CTL COLUMN SWITCHES NOW WORKED NORMAL. THE AUTOPLT ALSO CHKED NORMAL. ABOVE 18000 FT; I HAD THE FO CONTACT MAINT CTLR THROUGH DISPATCH AND DISCUSS THE EVENT AND ALL APPLICABLE IMPLICATIONS THAT WOULD EFFECT RETURNING OR CONTINUING TO DEST. IT WAS DETERMINED THAT SAFETY WOULD NOT BE COMPROMISED AND WE CONTINUED TO ORD. APPROPRIATE LOGBOOK ENTRY WAS MADE. THE ACFT WAS TAKEN OTS AT ORD.