Brake and battery light come on on 2002 Mitsubishi Montero Sport

The battery and brake light came on at the same time. One week prior to this it wouldn't start, my husband tapped starter than it started. Had battery,starter and alt checked at AutoZone who stated all were good. PLEASE HELP!! What could this mean?

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2 answers
When both the battery and brake light are illuminated with the engine running it is usually a sign of an open circuit/no charging condition in the alternator itself. With the engine running watch the dash warning lights, get your husband to hit the alternator gently and see if the lights go out and the battery meter now reads charge. If so it is a connection in the alternator and the alternator should be replaced.
I have a 01 Montero Sport LS and just replaced the B2S1 02 sensor and the very next day, Yep, the Batt/Brake lights came on. They have come on before but went off. Well, long story short the problem was the alternator.
There are other reasons to cause this but, if you have to change it out, don't listen to all these others about taking the fan off and shroud, an all that junk. All you need to do is remove the pass tire, remove the two line /hose brackets(remove the bolts) from up top, loosen the alt tensioner pully a bit then loosen from the bottom, the other tensioner bolt then remove the belt from the alt. then remove the two alt bolts and take it out from the side. Don't forget to remove the wires and plug in.