What was found
(CAN) WHEN SELECTING SURFACE DEICER TO EITHER MANUAL OR AUTO IN CRUISE THE WING DEICER BOOTS VISUALLY DO NOT INFLATE AND "MASTER WARNING" CAME ON. ON GROUND FUNCTIONED OK. FURTHER INVESTIGATION FOUND THAT AT CRUISE SPEED THE DEICER DISTRIBUTOR VALVE SOLENOID FOR WING INFLATION WAS NOT CLOSING COMPLETELY WHICH ALLOWED BLEED AIR TO BE DUMPED OVERBOARD INSTEAD OF TO BOOTS. VALVE REPLACED. ALSO A SMALL HOLEWAS FOUND IN BLEED AIR WARNING SENSE LINE. THUS WITH BLEED AIR BEING DUMPED OVERBOARD AND A SMALL HOLE IN BLEED AIR SENSE LINE, THIS WOULD MOMENTARILY TRIGGER THE BLEED AIR FAIL PRESSURE SWITCH WHICH ILLUMINATED THE "MASTER CAUTION", BUT NOT THE "BLEED AIR FAIL" LIGHT.