just noticed on my way home tonight that my battery light was flickering on and off. i would sit at light and it would go away and then i would move and it will flicker. i just put in a new battery last year. i don't know if it has to do with the tt setup and some of the electronics i put in. just wondering if anyone has some ideas.

 

sounds like an alternator going out. battery light comes on when voltage is low while the vehicle is running. the battery is essentially for starting the vehicle and storing electrical power, the alternator is for constant power output and charging the battery while the vehicle is running. a loose electrical connection and/or battery problem is possible also. most shops can perform an electrical systems check which checks the battery, alternator, starter and electrical components. my shop charges less than $30. hope this helps.

 

you can get a battery tester online for like $100... if you own several
older cars it's a nice thing to have. esentially tests wat the above
poster said.

 

well thanks for the help but here is another twist. now the parking brake light is on as well as the battery light. i'm stumped

 

+1, sounds like an alternator going out. Take out the alternator and bring it to an autozone/pepboys/kragen to get it tested. The test is free.

 

I have replaced my altenator on my G37. My mechanic apparently didnt tighten the battery cable that attaches to the back of the altenator. And also didn't push the clip completely in. Prompting us to take out the new one and have it tested. It tested good. But I'm still getting my battery light coming on and the brake light as well. The altenator is pushing out 14.2v at the battery terminals. And the lights are still flickering... any ideas?

 

Brake light is separate from the battery light, not very familiar with the G37 but since it shares the same V36 platform as the 2007-2008 G35 I'd suspect the brake fluid level switch is being triggered from low brake fluid in the reservoir.

Battery light though the circuit is pretty simple, big wire with the nut, small wire with the harness. However there's also an engine bonding jumper from the right side timing chain cover that lands on the chassis next to the engine that is also part of the circuit. It's probably in the same location on the G37.

This sends power to the instrument cluster which has it's own computer and it determines when/if the lights need to turn on.

Also sounds like you need a new mechanic since he doesn't know how to perform basic repairs.