First check your battery. Could it be old and not fully charged or have a bad cell. Put a charger on it for a good while or overnite then try cranking. If your engine is not charging the battery , it will run off of the battery for awhile but eventually drain it. If.that works have the battery checked at an auto supply store. You may also have to check your charging circuit. While charging the battery, check fuses with a meter to verify that they are not blown. Come back and let us know if that solves your problem.