A319 FLT CREW HAS A TOGW MISMATCH BTWN THE 2 FMGC'S.

Narrative

GOT A MESSAGE ON MCDU THAT SAID FMGC 1/2 TOGW MISMATCH. HAD THE SAME MESSAGE SEVERAL WKS AGO ON ANOTHER ACFT; AND WHEN I CALLED MAINT ON THAT OCCASION I WAS DIRECTED TO RETURN TO THE GATE; WHERE A 3 HR DELAY ENSUED WHICH DID NOT FIX THE PROB; AND I CANCELED THE FLT. SINCE THAT FLT I DISCOVERED THAT THE FIX FOR THAT ISSUE IS RELATIVELY SIMPLE; AND HAD BEEN PUBLISHED IN A COMPANY PUB; BUT WAS NOT MADE PART OF THE MEL PROC FOR A FLT QUANTITY INDICATOR CHANNEL INOP; WHICH CAUSES THE SUBSEQUENT MESSAGE DISPLAY. NOR WAS IT MADE AN ADDITIONAL PROC IN THE FLT MANUAL THAT I AM AWARE OF; BUT THAT DOESN'T MATTER. THE ISSUE IS THAT IT IS NOT PART OF THE MEL DEFERRAL PROC AND HAS CAUSED FLT DELAYS/CANCELLATIONS THAT COST TIME AND MONEY. WHY THE PROC IS NOT INCORPORATED; I DON'T KNOW; BUT UPON GETTING THIS SIMILAR ISSUE I USED CAPT'S AUTH TO SIMPLY INPUT MANUALLY THE ACFT FUEL WT; WHICH GOT RID OF THE MESSAGE; AND WE TOOK OFF INSTEAD OF CALLING MAINT; WHO MIGHT HAVE HAD ME RETURN TO THE GATE. I HAVE NOTIFIED MAINT OF THIS OMISSION AND WILL ALSO CALL THE FLEET TECHNICAL SUPPORT PEOPLE.