What was found
FAULT CODE 77-20862 THE BOTTOM LEFT EGT SIGNAL (T495S3) IS OUT OF RANGE ECONOMIC DEFERRED PER T/C 78273000. GROUNDED - YES. DEFERRED CODE PLT, ECONOMIC FAULT 500 FLT HRS, DEFERRED PER T/C 78273000. FOUND T49.5 S3 SIGNAL TEMP HAD ALL DASHES WHEN LOOKING AT CONTROL TEMPS. ACCOMPLISHED EGT CLEANING PER B737-800 AMM TASK 77-21-00-140-801. AFTER CLEANING S3 SIGNAL RETURNED. ACCOMPLISHED B737-800 FIM 77-21 TASK 803. NO FAULTS NOTED. TEMPS WITHIN TOLERANCES.