A: The fact that the vehicle starts right up with a jump tells me the starter and positive cable connection at the starter are in good condition. The battery needs to be retested, as well at the cable connections at the battery. Now, here is the tricky part. You say it only happens after the car has sat overnight. That points to an extraneous draw on the battery while the vehicle is at rest. The draw can come from anything from a lighted makeup mirror, to a phone that is left to charge inside the car overnight. A draw can even come from the alternator or a chafed harness. There are no published technical service bulletins for this problem. However, a good shop should be able to figure out the problem. Be aware you may have to leave the vehicle overnight at the repair shop.
Car Care Tip: When a repair shop asks to keep your vehicle overnight, be glad they are taking the time to check and recheck the repairs.
Larry Rubenstein is a master technician who owns a North Shore service station. His column appears every Saturday. Write to Larry at The Salem News, c/o Auto Scanner, 32 Dunham Road, Beverly, MA 01915, or send an email to firstname.lastname@example.org.