HELP! Battery and brake light come on, WHY??

Ok so I own a 99 Q45t with about 117k on it. Runs fine. Except for this intermittent brake and battery light thing. I searched and found what I suspected it to be, the alternator. BUT, when I had both the battery and alternator tested the tests came back good. They're both in working order. The alternator is charging like it should and the battery has good voltage. I've went to a couple places to check it out. One of which was an actual Infiniti dealership. But of course the lights weren't on when i got there. lol. So what are your thoughts on what it could be? I checked the brake fluid level and it's fine. But would that cause the battery light to come on as well? The only thing I could think of is that my passenger side foglights housing is broken. So maybe water got on the light or something and is shorting/grounding something out. The other thought would be a bad ground but it seems fine to me. Ugh, if someone could possibly shed some light on this it would be much appreciated. Thank you.

-Shonn

maybe the brake fluid low sensor?    I remember on my 02 Q45 my fluid was very low and my TCS and BRAKE and ABS lights all came on.

it's not low, but it is kinda dirty. Maybe i should just replace the fluid. hmmm.

may b intermit. problem with the alternator.

try starting the car and then popping the hood and disconnect the battery and if the car turns off its your alternator. it happened to mine so try that maybe

I think there is a recall on the alternator for catching on fire, so have the dealer run your vin and see if it has been done?? It would save you money when replacing the alternator:biggthumpup:

Well guys I took the negative off the battery with the car running and it didn't die. So alternator is good. I'm pretty stumped on what it could be. Any other ideas?

Just a really late update on the issue. It turns out that it was the alternator. The voltage regulator was bad and it was giving out too much power 15 volts or something. So I swapped out a new one and the lights went away. :)

Thank you for update...rarely people follow up on solutions

y33s are bad about alternators to begin with.....

thanks for the update!

yea no problem fellas. hopefully this will help diagnose problems for others. :)