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Q: Battery light on

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The other day one of my heater hoses broke from the connecter, spilling all the antifreeze all over , I replaced that , but now I'm having problems with the battery charging light coming on, I already replaced the battery and alternator, and old alternator tests pass, but when I tested it with the outside machine , it said voltage regulator failed, any suggestions? I asked all the guys at work , they don't even know smh.. help me

My car has 650000 miles.
My car has an automatic transmission.

Hello. If you continue to have a low voltage issue with the new alternator then there may be a circuit issue. Most of the time, if the alternator is good, it is the battery cables or there is an issue with the amp sensor on the battery cable. Most of the time it is a failure in the battery cables themselves. I usually do a voltage drop test on the battery cables first to see if they are bad. I replace them if they fail the test. If the cables are fine then I test the amp sensor which is the second most common cause of this. One of those two should be the problem. If you want to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose the battery light firsthand and help you make the necessary repairs.

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