Hey guys, I searched the forums for about 45 minutes looking for a post with an identical problem, but didn't find anything too similar. I need your help.

I have a 2006 G35 Coupe. Three days ago, the car wouldn't start in the morning. It had been sitting for about two days. She's my only car, and when I do drive it, it's usually traveling in traffic on the highway or local roads for an hour+ at a time. I went out of town for Thanksgiving for about 6 days, and since then have been driving the car every other day on average.

I have a ScanGauge II hooked up, and saw the battery was reading from 11.5 to 12.0 volts. (Usually, it's up around 14). The instruments in the car lit up, as did the door lights, but the car wouldn't turn over... just empty clicks. I jumped the car, and it started up fine. Took it about 15 minutes away, ran some errands for an hour and it started back up fine.

I drove it home, and the next morning, it wouldn't start. This time I had to leave the cables on for about two minutes before I had enough juice to jump the car. I drove for about 3 hours, left the car for 2, and it started right up. Drove another hour, and let the car sit overnight. She started right up in the morning.

The battery reads 14 to 14.3 volts when running, and bumps down to about 13 or so when I take the key out. Here's some other information I think is relevant:

I live in NY and over the last three days it has been below freezing outside.

I have multiple gadgets hooked up to the car: Zune charger, Valentine One, TomTom GPS, and a cell phone charger. (I've had everything plugged in at all times, and have been driving the car for almost a year without this ever happening). Since the second time I jumped the car, when I park I unplug all of the accessories, starts with no problem. Does this have anything to do with needing to be jumped?

While searching the forums I read the car has an "accessory mode". Did I accidentally activate something that can drain the battery when the car is off and sitting at night with no key in the ignition?

I haven't yet brought the car to the auto parts store to get the battery tested. Is it possible I have a battery that won't work in the cold weather? I bought the car in NJ and do not know where the previous owner lived.

If the battery is indeed the issue, is it possible that it won't work for two days and then work fine after that?

Thanks for your help guys and gals!

Jay

 

It sounds like the battery, but the easiest way to find out is to get it tested. Just take a socket set with you, drive to a auto parts store, take the battery out, and have them test it (they may test it while it is still in the car). Or you could buy a tester and test it yourself.

 

I strongly suggest taking your battery to a local shop to have it checked. I would not buy it from Sears as they charged me to install it $30-$40. When my QX56 needs a new battery I will get it from Sams as they have the Optima batteries I should have bought instead of the super expensive one from Sears.

 

Most batteries tend to live only 4-5 years....so yours is right in the range of needing replacement.

I'd get it tested first.

Another possibility is that you have a short in the electrical somewhere to ground causing a drain. To check this, you need a DMM that measures Amps in DC current. SImply unhook the neg of the battery and connect the meter in series and see how many amps of power the car draws in a rest state.

More than likely, the battery will test bad.

 

I've had a battery go bad after 4 years. I hadn't driven it for 1week before a vacation, and on the first day, I had to jump it.

thouht I would get it replaced before leaving town. Sam's club wouldn't do it, since it wasn't just a pull our/drop in. I instead bought a battery powered charger, which I used once on the trip. When I returned, it was tested and replaced.

 

Sounds like one of the cells in your battery is dead. On a warm day your car will probably start fine with just 5 cells. When it's cold out your car needs more cranking amps to get it started, so it will need all 6 cells working. Get the battery checked out. Autozone will do it for free, but you have to remove it from the car yourself. Since Winter is around the corner, I suggest you get it done ASAP. I just replaced my battery a month or so ago. I drove to Autozone and replace the battery myself in the parking lot.