Car battery has been draining after running then shutoff sitting in driveway after a period of time. Charge battery with trickle charger then battery voltage is 12.5v car starts. Car dash reads 13.5-14v while running sometimes drops to 12.5 while idling in traffic There is an ignition interlock installed for past 2 months however this issue just started the past 3 days. Dies battery need to be replaced or is the alternator failing?
Thank you in advance
My car has 80000 miles.
My car has an automatic transmission.
It sounds like your alternator may not be charging quite as effectively as it should be. The drop in amperage at idle is not necessarily unheard of but could be the beginning of it starting to fail. The voltage when running seems to be normal as 13.5 to 14 is within normal range. The battery drain while sitting may suggest that the battery is slowly beginning to fail. I would recommend having an expert from YourMechanic come to your location to diagnose your charging system.
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