the first thing i checked when car would not start,was timing belt,and timing marks.i replaced timing belt about 500 miles ago,and i had not retorgued belt yet,so i assumed belt had jumped.that was not the case.the next thing i checked was fire at plugs.all plugs have good spark.i have worked on american cars all my life,im 59.i have rebuilt,and restored 1968 corvette,1962 impala,and 1969 charger.i am 100% 321 code was not on car untill starting promblem 4 months ago.so your telling me the green/red wire to starter,means someone has already done wiring to starter from csv.another post on here says volvo can zap computer after wiring starter,so 321 code does not come up,maybe this is the case,i dont know.thank you so much for your help!