i got the Battery and the brake light on and they flicker faintly.
Whats going on here?

Cant find the answer in the mechanics manual.

If helps: '04 G35 coupe MT

 

bump

 

try replacing the battery

 

I would test the alternator to ensure it is putting out to spec.

 

your alternator is likely dying ^

 

Same thing happened and is still happening to me...I think the alternator is not putting out as much as it's getting. That's what the dealership told me but it happpens once in a blue moon. RIGHT after a new radio and amp install. What happened with yours??!

 

Bump.
My brake light and battery light came on while driving today, the voltage is running .5-1v high (usually around 15). I'm guessing this is the voltage regulator in the alternator gone bad? ...I had it scanned and it's not throwing a code though...???

 

Got it...blown atlernator fuse under the hood... just in case anyone else has this problem...

 

where is the fuse under the hood?

 

he hasnt logged in for 10 years.

 

You need to remove the plastic cover next to the battery to access the IPDM and fuses.