What was found
OAK/SUN FLIGHT NR 2409: DURING LEVEL CRUISE FLIGHT AT 25,000 FT, NR 2 BLEED HOT CAUTION ILLUMINATED AND REMAINED ILLUMINATED WITH NR 2 BLEED SWITCH OFF FOR DURATION. FLIGHT DIVERTED TO BOI. MAINTENANCE FOUND CDS MESSAGE B BLD ANA OT. REMOVED AND REPLACED RIGHT BLEED OVER TEMP SWITCH AND RIGHT PRECOOLER TEMP SWITCH (P/N 820907-5). REF Q400 FIM 36-11-16-810-802 PARA 1 THROUGH 4A, STEPS (1) AND (2) AND PARA 5. NO CDS FAULTS. AIRCRAFT RETURNED TO SERVICE.