What was found
LEFT WING A/ICE (C) MSG CAME ON IN FLT. C/W QRH. MSG PERSISTS. WERE IN ICING CONDITIONS. CLIMBED TO HIGHER ALTITUDE TO LEAE ICING CONDITIONS. LEFT FUSELAGE AND WING SHOWED IN AMBER. AFTER CLIMBING ABOVE ICING CONDITIONS RCVD L WINGA/ICE, R WING A/ICE + ICE (C) MSG WITH BOTH WING+COWL WAS ON POSITION. AS WE INSPECTED WING FROM THECOCKPIT IT APPEARED CLEAN OF ICE. AIRCRAFT REMOVED FROM SERVICE PERFORMED OPS TEST OF ICE DET. SYSTEM IAW AMM 30-81-00, AND TEST OF WING ANTI-ICE IAW AMM 30-12-00 AND ENGINE COWLS TEST IAW AMM 30-22-00, ALL CHECKS GOOD. REMOVED PLACARD AND FROM MEL.