As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX FLIGHT NR 2422: DE-ICE PRESSURE CAUTION LIGHT ILLUMINATED. SELECTED BOOT AIR SWITCH TO ISO PER CHECKLIST. DE-ICE PRESSURE READS 18 +/-3 PSI ON BOTH SIDES. THE ONLY BOOT INDICATOR THAT FAILS TO ILLUMINATE IS THE INBOARD TAIL BOOT ON THE NR 2 HORIZONTAL STAB. MAINTENANCE REMOVED AND REPLACED THE 35 DUAL DISTRIBUTOR VALVE IAW TASK 30-11-16-000-801 AND 30-11-16-400-801. OPS CHECK GOOD. AIRCRAFT RETURNED TO SERVICE.