The Battery and the Brake light are on at the same time for my 2002 Maxima. I understand that it might mean my alternator is going bad but I got it checked out by Triple A and their scanner read it as good. It’s charging my battery and I don’t have any problems with power at all. Any suggestions?

 

Check it yourself. If it's not at least mid 13s at warm idle (I believe 13.6 is the technical cut off point), then it's failing or you have some ****ty connections.

 

Did AAA test it with a load on it? Meaning, turn on everything in your car like headlights, stereo, rear defrost, heater etc and see what the voltage says...

 

Yeah they did. Exactly the way you describe it. Above is the receipt for it

 

15V is too high. The VRM is bad. The ECU does not like overvolting. If it goes high enough, it'll throw the car into limp mode.

Normal range is 14.1-14.7. At max load it's 13.5.

It's kind of obvious if lights/accessories are on and V doesn't drop at all, especially when it's out of range already.

 

Where can I find the VRM? Does this mean I have to replace the alternator?

 

Yeah, replacement time.

 

Crazy how I just went thru this situation on Sunday. Kinda figured something electrical was going wrong on my car as at times it absolutely had no power. Then all of a sudden the brake and battery light came on blink for a few, went off and came back on at idle. Didn't think anything until I tried to accelerate and the car wouldn't go anywhere. Long story short I cleaned the battery and alt ground wires and got it tested in which AutoZone said the alternator is bad. So I grabbed a good one from the pullapart and now no more warning lights

 

Regarding the status of the battery, I see that the measured CCA is higher than the rated. Is that normal?