Car not starting in very cold weather on 2005 Scion tC

Battery top condition, alternator new, fuel pump new and working properly, spark plugs new. I bought a heater for the oil pan and that didnt work. I think it might be another electronic problem? If it is above 10F it starts and runs great.?

Asked by for the 2005 Scion tC
SEEK DAIG WHEN CAR WILL NOT START. SORRY IM IN CALI WHERE ITS 80 TODAY