a) Get a trickle charger if you're going to leave it that long again.

b) Are you connecting the ( - ) cable to the negative terminal of your G, or to the frame?

G

"If my critics were told I could walk on water, they would say, 'But he can't swim.'"

Black/Willow Sedan. Check profile for specs.

<font color=red>B.A.S.T.A.R.D Squad</font color=red>

 

DON'T GET A TRICKLE CHARGER!!!! Here's a link to everything you need to know about dead batteries and what you should consider doing:

http://www.mpt.org/motorweek/goss.shtml

Text from the article:

There have been amazing changes in cars over the years, and that's really evident when it comes to the electrical systems. One of the things that we're really concerned with, well, that's the computer or computers, because many cars will have multiple computers in them.

Well, you may have problems with a dead battery or something. One thing you don't want to do is to use your old fashioned booster cables on a modern car, because you can damage electronics. What you should be using there is one of these booster packs. Very safe, it does a good job and it won't damage anything.

Now the batteries themselves have changed over the years, in as much as modern batteries may not give you any warning before they fail. One minute they're good, the next minute they're bad. Now one thing that is very common, you may have an automobile that is collectible or a boat or an RV or something that doesn't get used but has a battery in it. It just sits.

Well, the battery goes dead. What do you do? Well, you can recharge it. Of course you could use a big commercial charger like this [left]. It works well to recharge it, but this is no good to maintain the battery, to keep it from going dead again. So what do a lot of people do? Well, they go out and buy one of these trickle chargers [right]. Well, they're pretty neat. They're small, they're inexpensive, but they're deadly to batteries. Even if it only produces a tenth of an amp, over time it will overcharge and damage your battery. So how can you maintain a battery in something that doesn't get used on a regular basis?

Well, here we have a battery maintainer. This one is from Griot's Garage. Now the difference here is when the battery is fully charged, a battery maintainer shuts off completely. Then when the battery discharges, it turns itself back on. That way it doesn't overcharge the battery. These are very good for cars that are collectible. They're good for boats and RVs or anything that has a battery where you don't use it on a regular basis.

If you have a question or comment, write to me. The address is MotorWeek, Owings Mills, MD, 21117.


'98.5 Contour SVT, 132K miles (Sold)
'04 G35 6MT - Black on Black

 

I think the key to the above article is to avoid overcharging the battery. Not all trickle chargers are going to necessarily put out 100 milliamps regardless of the capacity of the battery. A quality trickle charger should reduce its output as the battery comes up to charge. Somewhat similar to the battery maintainer mentioned in the article, except that it would not turn itself off / on.

At the same time, there is no need to use any charger if the car is being used daily for more than just moving it in and out of the garage.

 

I agree that overcharging lead-acid batteries is the worst thing you can do to them, but I don't understand Motorweek's comment about not using booster cables.

What's the difference between using a booster cable (connected to a good battery on the other end), and using one of those booster packs (which is also just connected to a good battery on the other end)?!

<font color=blue>'04 G35S 5AT, Black Obsidian/Willow, Prem/Nav/Sat</font color=blue>