Infiniti G37 dead battery again.

[N80]

I have a 2009 Infiniti G37 coupe with a manual transmission (a dinosaur by today's standards) that I love. Got it used about 4 years ago. It is my wife's car. Low miles when I got it and we still don't put a lot of miles on it but it gets driven almost every day.

For the last two years it has been ruining batteries. Cheap batteries. Posted a while back about terminal clamps not fitting properly. Got a new, cheap, battery. Worked fine for about 6 months then crapped out. Got a middle of the road battery, started to fail immediately, took car to Nissan dealership. They said it was the wrong kind of battery (???). The place where we bought it acknowledged this and gave us a new, correct battery. Now that its cold, it is failing. Had to jump it yesterday.

Car functions properly otherwise. No warning lights. No codes. Wife, who has to deal with all this, called local Nissan dealership that we have dealt with a lot. They said they could run an expensive diagnostic and would still not likely find the problem and said not to waste our money and that we needed to take it to an Inifiniti dealership (an hour away). ?????

Battery takes a jump and charged fully off my trickle charger.

So......questions..........how does one go about finding what is draining the batteries in this car........very slowly and over long periods of time? Seems impossible to me. Second question, would buying a high end, high amp (or whatever spec) battery be likely to change anything or would I just be ruining a more expensive battery? Any thoughts welcome. We love this car and would hate to have to sell it...................you can't find them with manuals anymore.

 

[aczlan]

Disconnect one battery terminal (key off and out), turn off the dome light(s), connect an ammeter between the battery and the terminal and see how many milliamps are being drawn. If its more than 40-80 milliamps, start pulling fuses to see what circuit is causing the problem.
I would also have the alternator checked to make sure it doesn't have a diode going bad which can fry a battery (put a meter set to AC Volts across the battery terminals with the engine running and see how many volts it reads, should be under 2 volts).

Aaron Z

 

[N80]

Okay, that is a plan I can get my head around. But, as I've stated before, I am marginally intelligent and a serious DIY'er but I'm a bona fide idiot when it comes to electricity. Do you have a recommendation for a reasonably priced ammeter and where is a good place to get one, is this testing done with the engine on or off, is it done with whatever the fuse is running on or off (radio, AC, heat warmer, etc)?

Thanks!

 

[RNeumann]

Not trying to be a jack wagon- but if the above (correct way) doesn’t make enough sense to you causing you to question whether or not to do this with a running vehicle or not (vehicle off) I’d suggest taking it to a shop that can do the above test.

If you are still thinking this is something you want to tackle I’d suggest starting with the basics of DC current in a vehicle (chassis ground) and work your way up from there. I’m guessing after 4-8 hours of YouTube you will understand enough to tackle your issue.
Btw- a reputable shop with a good tech should be able to isolate your issue in well under an hour. The time to make the fix will depend on the issue. It’s not some expensive test as your dealer/stealer is suggesting.

 

[N80]

Not trying to be a jack wagon- but if the above (correct way) doesn’t make enough sense to you causing you to question whether or not to do this with a running vehicle or not (vehicle off) I’d suggest taking it to a shop that can do the above test.

I don't mind hiring out what I don't understand, and I'm sure my question exposes my lack of understanding, but the procedure he described is simple enough if I know the specifics (whether I understand them or not.)

If you are still thinking this is something you want to tackle I’d suggest starting with the basics of DC current in a vehicle (chassis ground) and work your way up from there.

I do have some basic understanding. Have wired winch into pick-up truck, with proper fuse, ground, all that. Cookbook type stuff. I can follow a recipe.

Btw- a reputable shop with a good tech should be able to isolate your issue in well under an hour. The time to make the fix will depend on the issue. It’s not some expensive test as your dealer/stealer is suggesting.

Well, not a knock on all dealerships but I find the level of competence in many of them to be sub par and this guy clearly did not want the job. And I understand the test may not be expensive but in my experience I'd guess this dealership, although generally honest, would take two hours. Two hours of moderately competent labor at a dealership already expecting not to be able to handle the problem would probably be a waste of several hundred bucks that they don't refund if they can't find the problem.

I do have a reputable, honest and competent general mechanic that I can take it to to do the testing you guys describe but he is not into the high tech stuff, so if it is something in the GPS or engine management he would not be able to fix it.

I'm game to do the job and probably need an ammeter having as many vehicles as I do and a general inclination to work on them myself.

Thanks again.

 

[N80]

Okay, re-read. Now understand process. Was at work when I posted this. All of this sounds easy enough for me to do at least to get pointed in the right direction.

Now another question, theoretical: If I do both tests aczlan recommended, and they are both within normal limits, is there any chance that a beefier battery would help. The reason I'm asking, and this may be nonsense, but this car has always been harder to start than my other similar cars....but not by much. In other words, with my 350Z you hear the starter spin and immediately it fires up. The G37 always seems to take a fraction of a second or maybe an additional spin or two of the starter to turn over. Most people probably wouldn't notice it at all but it is clearly different. Granted, my 350z and previous two Infinitis were 3.5 liter engines and that may be the only reason there is a difference. But the G37 takes longer to start even than my pickup trucks. It is also worse on cold days.

So my thinking (which may be backward) is that maybe with each start there is too much strain on an underpowered/cheap-o battery and that is wearing them out faster? Not sure it would since it gets recharged while the vehicle is running. Just a thought.

 

[RNeumann]

Ok I like the fight! Any good auto parts store or hardware store will have good “multimeters”. These will check AC and DC voltage, amps and ohms. Digital meters are generally considered better however some lower end units may not display quick and or little spikes. With that if you want a $10-$20 unit I’d be tempted to get an analog needle style. If you want to spend a bit more (and you do!) get a digital meter. With a little love the tool will last more than a lifetime. I still have and use the one I got when I was a teenager. If you are a top of the line guy Fluke makes nice stuff. They do make meters that will do a lot more but rarely does one run into a situation that would warrant the extra cost.
Any diagnosis should be done with a systematic approach. Write down the results as you go along.
Good luck and keep us posted!

 

[RNeumann]

Okay, re-read. Now understand process. Was at work when I posted this. All of this sounds easy enough for me to do at least to get pointed in the right direction.

Now another question, theoretical: If I do both tests aczlan recommended, and they are both within normal limits, is there any chance that a beefier battery would help. The reason I'm asking, and this may be nonsense, but this car has always been harder to start than my other similar cars....but not by much. In other words, with my 350Z you hear the starter spin and immediately it fires up. The G37 always seems to take a fraction of a second or maybe an additional spin or two of the starter to turn over. Most people probably wouldn't notice it at all but it is clearly different. Granted, my 350z and previous two Infinitis were 3.5 liter engines and that may be the only reason there is a difference. But the G37 takes longer to start even than my pickup trucks. It is also worse on cold days.

So my thinking (which may be backward) is that maybe with each start there is too much strain on an underpowered/cheap-o battery and that is wearing them out faster? Not sure it would since it gets recharged while the vehicle is running. Just a thought.

No chance....u r scaring me again.....haha
Keep asking the questions and the TBN peanut gallery will come through

 

[N80]

No chance....u r scaring me again.....haha
Keep asking the questions and the TBN peanut gallery will come through

So an underpowered battery will last as long as a higher powered one? It might be true but certainly isn't intuitive.

Anyway, any reason this item would not be sufficient for my infrequent use?

Amazon.com: INNOVA 332 Auto-Ranging Digital Multimeter: Automotive

As an aside, my Kubota L4400 is still on its original battery. It is 10 years old and goes weeks without use. Go figure.

Edit: I looked at the Flukes. Good stuff. More than I can afford. This Innova brand makes a more full featured unit for $75 but I have no idea what I'd be getting for the extra $50.

 

[RNeumann]

So an underpowered battery will last as long as a higher powered one? It might be true but certainly isn't intuitive.

Anyway, any reason this item would not be sufficient for my infrequent use?

Amazon.com: INNOVA 332 Auto-Ranging Digital Multimeter: Automotive

As an aside, my Kubota L4400 is still on its original battery. It is 10 years old and goes weeks without use. Go figure.

Edit: I looked at the Flukes. Good stuff. More than I can afford. This Innova brand makes a more full featured unit for $75 but I have no idea what I'd be getting for the extra $50.

Your little motor uses a gear reduction starter that doesn’t pull that much when compared to standard starters and or larger motors. You have a short that is killing the battery- it’s not the battery size. The only thing a bigger battery will do is take a bit longer to kill and cost you more money.

With regards to the meter- save the extra $50. The links shows a meter that will do what you need and is highly rated.