A dead battery after a couple of weeks could be due to a faulty battery or parasitic draw. Undercarriage washes help remove salt and sand, while spray wax is minimally effective and can smudge glass.

Car Bluetooth systems drain batteries even when vehicles are off, costing $200-400 in replacements plus potential towing fees ...

In this video, I demonstrate how to fix a parasitic battery drain by installing a battery quick disconnect or kill switch.