A B737-200 HAD SEVERAL SYSTEMS INOP SUSPECTED TO BE CAUSED BY THE STATION GND PWR UNIT.

Narrative

RECEIVED ACFT IN ABE WITH THE ACARS SCREEN BLANK. CONSULTED MEL AND DETERMINED WE COULD GO WITH IT INOP AND WRITE IT UP IN ABE. WE (CAPT AND MYSELF) ALSO OBSERVED WE HAD NO DME SIGNAL; WHICH WE ATTRIBUTED TO THE VOR BEING NOTAMED OFF THE AIR. ONCE AIRBORNE IT WAS APPARENT THAT WE HAD; IN FACT; LOST BOTH DME RECEIVERS. WE ALSO OBSERVED THE OIL TEMP GAUGE GO TO FULL COLD OFF SCALE AND THE CHIME SYSTEM CIRCUIT BREAKER POPPED. (WE WERE INFORMED THAT THE CHIME SYSTEM WAS INOP BY THE FLT ATTENDANTS.) WE CONTACTED MAINT CTL AND WERE SUBSEQUENTLY DELAYED FOR +8 HOURS IN MDT. IT IS MY OPINION THAT A BAD POWER SOURCE IN ABE OR A BAD GCU IN ACFT (HAD HISTORY OF ELECTRICAL PROBLEMS) CAUSED THESE FAILURES. THE LESSON TO BE LEARNED HERE IS THAT ONE MUST EXERCISE VIGILANCE WHEN DEALING WITH MULTIPLE FAILURES OF UNRELATED COMPONENTS AND KEEP THE #1 PRIORITY IN FOCUS: 'FLY THE ACFT FIRST.' CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ACFT WAS A B737-200 AND WHEN THE PREFLT CHECK STARTED IN THE MORNING SEVERAL SYSTEMS WERE INOP. THE RPTR SAID THE FOLLOWING SYSTEMS WERE INOP: CABIN CALL CHIME; BOTH DME SYSTEMS; AND ONE ENGINE OIL TEMPERATURE INDICATOR. THE RPTR STATED THE STATION GND PWR UNIT WAS SUSPECTED OF NOT SUPPLYING QUALITY PWR AND THE ABOVE ITEMS WERE DEFERRED. THE RPTR SAID AT THE NEXT STATION THE MAINT CTLR; WHEN ADVISED OF THE INOP SYSTEMS; STOPPED THE ACFT FOR A POSITIVE FIX. THE RPTR STATED THE FIX WAS THE REPLACEMENT OF THE OIL TEMP INDICATOR; BOTH DME UNITS; AND A CALL CHIME. THE RPTR SAID A REPORT WAS SENT TO THE OVERNIGHT STATION FOR AN ELECTRICAL CHECK OF THE GND PWR UNIT USED ON THE ACFT.