Q: I changed the alternator a month ago but the battery light came on recently and now the car won't stay on

asked by on November 05, 2016

Had to keep getting a jump so i changed my alternator. A month later my battery light came on for the first time. It goes off when i rev the engine and comes right back on. I gt a new battery in February and new alternator in October. Car starts when i gt a jump but lights are very dim and car shuts off after a few minutes of being on. I cant keep dishing out money to fix this car. Please help.

My car has 300000 miles.
My car has an automatic transmission.

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The problem sounds like the alternator has failed and stopped charging. Your alternator should be tested to see if it is putting out any voltage and amperes to recharge the battery. You should also make sure the main cable off of the alternator is not shorted out between main fuse panel and alternator. Replace the alternator and retest the system after recharging the battery.

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