HELP??? My 2009 G37 has been starting a little sluggish, then not starting at all. The battery is less than 6 months old and still test good. Heard possibly it could be the amp to the Bose system. Heard that if the amp goes bad it can drain the battery all the time. We unplugged the fuses that goes to the amp but I am still having the same problem. I am tired of carrying around jumper cables but not a choice when the car decides to start and not start when it wants. Any suggestions as to what might be draining the battery down.

 

What's the voltage across the battery when the car is running? Maybe you have a bad alternator.

 

Yeah sounds like an alternator problem

 

How many amps is the battery rated at, and how many is it producing under load? There should be a sticker on the battery that tells the specifications, which are important. A brand spanking new 550 CCA battery is going to be about as good as a half-bad 700 CCA battery. Whats the electrolite & acid level in the cells? Have you (or mechanic type) tested each cell with a hydrometer and determined each cell to be good when fully charged? What group battery is yours? Whats the make & model name of it? If the cells were low, did you add water?

Just because a 12 volt battery registes 12 volts with a test light does not mean its "good". An auto parts store will need to put a load test on it and each cell needs checked out. Even if it tests OK, if its under-rated for the car, it won't do you any good.

What, if any, non-OEM electronics are installed on the car? Remote start? Alarm? I've not heard anything about the Bose amp being troublesome but who knows. In fact I thought there were multiple Bose amps in the vehicle, not just one.

Whats the condition of the cables? Are the cable ends stock or have they been replaced? Are the cables tight? Have you checked ground and cleaned ground points? Is the battery secure down with the stock cross bar and J-hooks?


Without having a better idea of what you've tested/looked at/determined, I'm not sure how you'll get much solid advice.

 

Look into the vent control valve issue.