What was found
REOCCURING DEICE PRESSURE CAUTION LIGHT, POWER RATING DETENT CL, OCCURED AT -6000' AND 13000 ' IN SLOW AIRFRAME MODE SELECT. RETURNED TO FIELD. LANDING UNEVENTFUL. PERFORMED TACTILE INSPECTION OF ALL DEICE BOOTS WHILE INFLATING BOOTS. DEICE BOOT 613AR & 613BR DID NOT INFLATE. CHECKED CDS FOR FAULTS, FOUND NO FAULTS. REMOVED L/E PANEL 613AR IAW AMM TASK 57-23-01-000-801. R & R NR 2 DDV IAW AMM TASK 30-11-16-000-801 & 30-11-16-400-801. NO HELP. R & R TMU IAW AMM TASK 30-11-01-000-801 & 30-11-01-400-801. NO HELP. CHECKED CDS AND FOUND FAULT CODE "LOW PRESS 2A". R & R NR 2 DDV IAW AMM TASK 30-11-16-000-801 & 30-11-16-400-801. PERFORMED OPS TEST OF THE AIRFRAME DEICE SYS IAW AMM TASK 30-11-00-710-804. OPS CHECK GOOD. ALL DEICE BOOTS INFLATED NORMALLY, ADVISORY LIGHTS NORMAL AND DEICE PRESS CAUTION DID NOT RETURN. TMU REPLACED AS A PRECAUTIONARY MEASURE. RETURNED TO SERVICE.