Narrative:

Master caution light flashed intermittently. Could not be silenced. Caused by #2 engine hydraulic pump light. Pumps worked well. Hydraulic quantity and pressure normal. Auxiliary pumps made no change so pump ok, just light problem. Went out en route. On landing in rdd, ca, called maintenance control. 'Probably a short in warning system.' because master caution affected, no deferral possible. Since light had gone out, we can fly it. They'll check it out in pdx, ok. Started in rdd for rdd-pdx leg, light came on again during taxi. We decided it was temporary and departed for pdx. During the entire flight, light remained on and flashing. Aircraft repaired in pdx. Didn't want to ground aircraft in rdd as no maintenance. I wanted to be on time in pdx to catch flight home (as passenger). We were 1 hour late into pdx anyway. Flight was otherwise uneventful.

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Original NASA ASRS Text

Title: A KNOWN ACFT EQUIP PROB THAT AFFECTED THE MEL REQUIREMENTS AND AIRWORTHINESS STANDARDS IS IGNORED AS DH-8 CREW TAKES ACFT FROM DEP ARPT TO DEST ARPT.

Narrative: MASTER CAUTION LIGHT FLASHED INTERMITTENTLY. COULD NOT BE SILENCED. CAUSED BY #2 ENG HYD PUMP LIGHT. PUMPS WORKED WELL. HYD QUANTITY AND PRESSURE NORMAL. AUX PUMPS MADE NO CHANGE SO PUMP OK, JUST LIGHT PROB. WENT OUT ENRTE. ON LNDG IN RDD, CA, CALLED MAINT CTL. 'PROBABLY A SHORT IN WARNING SYS.' BECAUSE MASTER CAUTION AFFECTED, NO DEFERRAL POSSIBLE. SINCE LIGHT HAD GONE OUT, WE CAN FLY IT. THEY'LL CHK IT OUT IN PDX, OK. STARTED IN RDD FOR RDD-PDX LEG, LIGHT CAME ON AGAIN DURING TAXI. WE DECIDED IT WAS TEMPORARY AND DEPARTED FOR PDX. DURING THE ENTIRE FLT, LIGHT REMAINED ON AND FLASHING. ACFT REPAIRED IN PDX. DIDN'T WANT TO GND ACFT IN RDD AS NO MAINT. I WANTED TO BE ON TIME IN PDX TO CATCH FLT HOME (AS PAX). WE WERE 1 HR LATE INTO PDX ANYWAY. FLT WAS OTHERWISE UNEVENTFUL.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.