What was found
(PIREP) SMOKE MASTER WARNING CAME ON DURING TAXI. F/A VERIFIED THERE WAS NO SMOKE. (MX) PERFORMED MASTER WARNING CAUTION LIGHT TEST IAW DHC-8 MM 26-12-05. ADDITIONAL NOTES: TWO DIFFERENT P/N SMOKE DETECTORS ON BOARD THIS AIRCRAFT. NR 1 - P/N 30-231-3, S/N 35007 TIME SINCE REPAIR 174.8 HR. NR 2 - P/N 473054, S/N 0054W, TIME SINCE REPAIR 1326.8 HR. EXPERIENCED IN THE PAST THAT CELL PHONE USAGE TRIGGERS THE SMOKE WARNING AND BELIEVE THIS TO BE A DESIGN ISSUE. THEREFORE, DON'T KNOW WHICH DETECTOR (OR BOTH) MAY HAVE GIVEN THE FALSE WARNING, SO ONLY A FUNCTIONAL TEST ON THE DETECTORS WAS PERFORMED.