As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WING ANTI-ICE R VALVE CAUTION LIGHT ILLUMINATED DURING DESCENT WHEN WING ANTI-ICE WAS SELECTED ON. EXTINGUISHED WHEN WING ANTI-ICE WAS TURNED OFF. GROUNDED - YES. PILOT VERBAL- OPERATED NORM AFTER CYCLING BACK TO ON. THEN CYCLED ANTI-ICE SWITCH OFF & BACK ON A SECOND TIME & THE VALVE STUCK IN TRANSITION AGAIN. SUSPECT BAD "R WING ANTI-ICE VALVE". REMOVED & REPLACED RH WING ANTI-ICE VALVE. OPS CHECKED GOOD, LEAK CHECKED GOOD, 2X C/B RESET, A/C RETURNED TO NORMAL. REF B737-9 AMM 30-11-11.