While driving the battery light turns on and engine shuts off

TRAVIS BUTLER2

MEMBER
2003 MAZDA TRIBUTE
3.0L
V6
2WD
AUTOMATIC
95,000 MILES

Okay, we've replaced the battery the alternator but what it does is; it'll drive for a little bit like 20-30 minutes and then the battery light will come on stay on and then it will shut off won't start back up for a while and then it'll start back up. The problem seemed like it was fixed after the alternator was put in but the day after it's starting to do the same thing again. What could it be?

Sunday, February 28th, 2021 AT 5:48 AM

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

We need to do two things first and foremost before we can figure this out. Let's get the battery tested and if it is drained again, we need to charge it or replace it so that it is okay.

https://www.2carpros.com/articles/car-battery-load-test

Then we need to test the alternator and not run the vehicle for long periods of time as it will just drain the battery again.

https://www.2carpros.com/articles/how-to-check-a-car-alternator

Once we know if the alternator itself is ok, we can test the actual charging system when the engine is running by putting a meter on the battery and it should be 13-15 volts.

There could be an issue in the PCM but the voltage regulator is internal to the alternator so it would be the PCM not telling the regulator to turn the field control.

Let me know what you find. Thanks

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