dead battery from loose bolt connected to battery terminal . would that cause a dead battery and would it be worth replacing the bolt
Yes, a loose-fitting or corroded battery cable to battery post connection can certainly lead to a dead battery. Corrosion builds up between the battery post and cable, creating electrical resistance. This becomes harder and harder for the alternator to charge the battery, and eventually the battery discharges, and goes dead. Clean the connectors and replace the bolt and/or cable ends. The battery may be toast by now as well - have it checked. I would recommend a battery charging system inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose and correct this problem.
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