As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WING ANTI ICE "L VALVE" LIGHT ILLUMINATED WHEN THE WING ANTI ICE WAS TURNED ON. LIGHT TURNNED OFF WHEN WING ANTI ICE WAS TURNED OFF. GROUNDED - YES. PERFORMED LEFT WING THERMAL ANIT ICE VALVE HEALTH CHECK REF B737-9 AMM 30-11-11. OPS CHECK GOOD, AND INLET TUBE CLEAR. NO HISTORY 30 DAYS. A/C OK FOR SERVICE.