What was found
LEFT COWL VALVE OPEN LIGHT WILL NOT ILLUMINATE WITH ENGINE ANTI-ICE SWITCH ON, OR DURING LIGHT TESTS. FORWARD PANEL ANNUNCIATOR INDICATES ANTI-ICE IS WORKING NORMALLY. ACFT GROUNDED. HAS A HISTORY. REPLACED THE NR 1 ENGINE COWL ANTI ICE VALVE. OPS & LEAK CHECKED GOOD IAW AMM 30-21-11. FOUND ANTI ICE & RAIN ENGINE 1, ENGINE & WING CONTROL CIRCUIT BREAKER OUT. GVI BEHIND P18 PANEL GOOD. CIRCUIT BREAKER RESETS NORMALLY & STAYS IN IAW AMM 20-60-01. OPS CHECKED THE WING ANTI ICE VALVES, GOOD IAW AMM 30-11-00. OPS CHECKED COWL TAI VALVE DURING ENG RUN GOOD IAW AMM 30-21-00. CIRCUIT BREAKER STAYS IN.