CONFUSED BY THE EXISTENCE OF BOTH A FILED RTE THEY SHOULDN'T FLY AND CLEARED RTE THEY SHOULD HAVE ON THEIR ACARS DELIVERED PDC; MLG FLT CREW PICKS THE WRONG ONE AND HAS A TRACK DEV.

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CAPT AND I ARRIVED EARLY TO GATE AND HAD PLENTY OF TIME TO COMPLETE OUR DUTIES. I; FO HAD BEEN TO SJC SEVERAL TIMES BUT THIS WAS THE FIRST TIME I WOULD BE DEPARTING RWY 12L WITH THE TYPICAL BEING RWY 30R. THE EVENT STARTS WITH MYSELF OBTAINING THE PDC FROM SJC CLRNC FOR OUR FLT TO OUR DEST. THE PDC CONTAINED A CHANGE IN OUR RTE FROM THE FILED RTE WHICH WAS THE FIRST TIME I HAD SEEN THIS WHILE RECEIVING A PDC. OUR FLT PLAN WAS A (SEE FILED RTE) TO (CITY) AND OUR RELEASE HAD US FILED SJC.DANV2.LIN.PEONS.INSLO.DTA.J84.OBH ETC. THE PDC CONTAINED THE FOLLOWING: -ALTAM7.LIN.PEONS.INSLO.DTA- I WAS NOT FAMILIAR WITH THIS CHANGE FORMAT AND SUBSEQUENTLY ASKED THE CAPTAIN FOR HIS HELP. MY INEXPERIENCE WITH DEPARTING RWY 12L ALSO PLAYED INTO MY ASKING FOR ASSISTANCE. THE CAPT AND I DISCUSSED THE CLRNC AND ITS INTENT. I ASKED IF WE SHOULD JUST CALL CLRNC BUT THEN WE REALIZED WE HAD THE EXPLANATION ON OUR WX PACKAGE. THE CAPT READ THE EXAMPLE ON THE PAGE AND I FOLLOWED ALONG FROM THE FO SEAT. WE BOTH THOUGHT THAT WE UNDERSTOOD THE PDC AND SUBSEQUENTLY WENT WITH THE DANV2 AS OUR DEP SID. NORMAL PUSH AND START AND TAXI TO RWY 12L. NORMAL DEP AND CLBOUT. WE WERE BOTH UNSURE OF OUR EXACT ALT; BUT WE BELIEVE AT APPROX 5000 FT TO 6000 FT DEP ASKED US IF WE 'WERE GOING TO MAKE THE TURN.' WE REPLIED THAT WE WERE ON THE DANV2 WHICH WAS A RADAR VECTOR SID. CTLR ASKED US IF WE HAD RECEIVED THE ALTAM7 FROM CLRNC WHICH AT THE TIME WE WERE SURE WE HAD INTERPRETED THE PDC AS THE DANV2. DEP HAD US TURN TO 300 DEGS AND RESUME THE ALTAM7 DEP FROM THAT POINT. THERE DID NOT SEEM TO BE ANY TFC SEPARATION ISSUES AND THE CTLR SWITCHED US TO ANOTHER NORCAL DEP CTLR. NORMAL CLB FROM THIS POINT ON. UPON LEVELING AT CRUISE WE BEGAN TO LOOK AT OUR CLRNC; THE PDC MESSAGE AND AGAIN REVIEWED THE WX PACKAGE EXPLANATION OF PDC RTE CHANGES. IT WAS DURING THIS REVIEW THAT WE REALIZED WE HAD ERRED IN OUR UNDERSTANDING. WE HAD INDEED FLOWN THE WRONG SID AND HAD COMPLIED WITH THE WRONG CLRNC. AFTER REVIEWING OUR PDC AND THE EXAMPLE ON OUR WX PACKAGE THE PHRASEOLOGY IS CLR. HOWEVER; THE MINUS SYMBOLS DID LEAD BOTH OF US TO THINK THAT THIS WAS THE CHANGED RTE NOT THE NEW ROUTING TO FOLLOW. IN OUR MINDS THE NEW RTE WOULD HAVE BEEN SURROUNDED BY THE PLUS SYMBOLS. BUT TO AN EVEN GREATER DEGREE THAN UNDERSTANDING THE PDCS; A CALL TO CLRNC TO CLARIFY THE RTE WOULD HAVE BEEN THE EASIEST AND BEST WAY TO VERIFY OUR RTE. MORE DILIGENCE WILL BE MADE WHEN THE NEXT RTE CHANGED PDC IS RECEIVED.SUPPLEMENTAL INFO FROM ACN 775430: MY ONLY SUGGESTIONS WOULD BE A CLEARER FORMAT OF THE PDC. EITHER HAVE ONLY THE CLEARED ROUTING SHOW UP IN THE PDC MESSAGE; OR CLEARER ANNOTATION FOR THE REVISED ROUTING; SO THERE IS LESS OF A CHANCE THAT A CREW FLIES THE UNREVISED ROUTE.