Why is my brand new battery is going dead to a 1999 grand maquis
Your altnator my not be charging thus draining your battery. Your belt could also be loose....have the altnator load tested..
Clean battery cable connections are a must.You could have a parasitic draw on the system. With engine running you should have 14 to 14.6 volts measured at the battery terminals. If it is below say 13 volts (engine running) I would suspect the alternator is bad or the fusible link in the battery to alternator cable has an issue. If the voltage checks out look for a trunk light, glove box light or an under hood lamp staying on that could be running the battery down.
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