battery drain

[donk]

Dear all,
My son-in-law has a 98 with only about 35,000 miles and a new (last spring from the Acura Dealer) battery, however it seems to drain in as little as 2 weeks if the car isn't run. Relay clicks, but won't start. Any ideas from anyone?

Mine seems fine, 96 w/75,000 and a year old battery from of all places Sears Die Hard, (I didn't put it in, it was there when I bought the car).

As always thanks for all your input in advance, I am sure that he will appreciate it. He's a really busy guy and doesn't get much time with his car other than to drive it once in a while.

Regards,
Don

 

[ftuhy]

Check for things such as a trunk light or glove box light continuously on. Is the car all original, or was a custom sound system or alarm system added?

But, "off" current drains can vary from car to car a bit. My '96 takes about 4 weeks to discharge the battery.

Nothing wrong with a Die HArd battery. They usually come out fairly well in comparison tests.

Get a float charger or battery tender (not a trickle charger) for when the car is not in use. They vary in price from $7 at Harbor Freight (mine kept the llast battery surviving winter storage for 10 years) to lots more for ones that have more features, fancier leads, etc.

 

[omega2]

I had this problem for a while too. The easy solution was the float charger as previously mentioned (actually the Harbor freight one). In my case the positive battery cable wasn't clamping down tight enough due to the clamp stretching (original cable). You might want to pull on the cable to see if it easily slides off the positive battery terminal. Ultimately, I had the positive battery cable replaced with a new OEM one and haven't had the problem since.

 

[javajohn]

My 1991 has 20K original miles and the battery drains in about 4 weeks if not driven. I haven't found the problem but I installed a battery cut off switch and use it when the car will not be driven for several weeks.

 

[RPM217]

I had this problem with my 02, it would take 2-4 weeks and nothing but clicks. I used to jump start it regularly, got smart and got a CTEK, now after the OEM battery for 10 years, I just had Larry B replace it. Get a trickle/float charger and you won't regret it!!!

 

[donk]

Thanks Guys,
I know he will appreciate the info as do I. Headed to Harbor Freight today.
Warmest regards,
Don

 

[passline]

Nothing wrong with a Die HArd battery. They usually come out fairly well in comparison tests.

Get a float charger or battery tender (not a trickle charger) for when the car is not in use. They vary in price from $7 at Harbor Freight (mine kept the llast battery surviving winter storage for 10 years) to lots more for ones that have more features, fancier leads, etc.

The Die Hard battery may be good but the Die Hard battery maintainer float-mode tender is a piece of crap. It would not keep any of my vehicles charged fully for them to crank. I will get 2 Harbor Freights for the Lambo and the NSX.

 

[ImolaOrange03]

Once in a blue moon, a battery CAN be defective. I would either put in another battery and try that first, or even putting another battery in the car. The battery is under warranty so the dealer can test the battery as well. I'd do this before going off and doing many unnecessary things. Simple as that. Eliminate that possiblility that the battery may be defective.

A long time ago, I was asked to help jump start Nicholas Cage's Porsche 928 GTS which was basically brand new with only about 600+ miles on it. I did jump start the car and drove it for over an hour before returning it. Nicholas arrived home an hour later, only to find that the 928 GTS wouldnt start...the battery was totally dead again. The next day the car was towed to the Porsche dealer only to find out that the battery was defective.

 

[nis350]

I had this problem for a while too. The easy solution was the float charger as previously mentioned (actually the Harbor freight one). In my case the positive battery cable wasn't clamping down tight enough due to the clamp stretching (original cable). You might want to pull on the cable to see if it easily slides off the positive battery terminal. Ultimately, I had the positive battery cable replaced with a new OEM one and haven't had the problem since.

I have a year old battery that needed a jump to start the car after about 4 wks.

Do you need to disconnect the battery from the car to use the float charger? Which model do you use from Harbor Freight? Thx.

 

[Briank]

I would not get to excited about the battery draining in 4 to 6 weeks. The normal drain of an NSX is 40 to 65 mA. That will drain a perfect battery in about 6 weeks.

The best way to see if you have an issue is to measure the drain with a mA meter. You will know right away if something is drawing a little more then it should.

The battery does not need to be disconnected when using a charger.

 

[Track Addict]

The normal drain of an NSX is 40 to 65 mA.

That's a great diagnostic piece of information...Thanks Briank!

 

[pgilliam1]

I would not get to excited about the battery draining in 4 to 6 weeks. The normal drain of an NSX is 40 to 65 mA. That will drain a perfect battery in about 6 weeks.

Would you know why this happens? I've never had a car that did this. Seems odd to me that the NSX drains batteries like it does.

 

[kreh]

What was the final result. Please post.

 

[Briank]

Would you know why this happens? I've never had a car that did this. Seems odd to me that the NSX drains batteries like it does.

I am not sure what the main culprit of the battery drain is but there are several things that have a part. Listing off the top of my head, the radio, the ccu, the ecu, eps and SRS have un-switched power to hold there memory. The Security system and the clock is also active all the time.

 

[pgilliam1]

I am not sure what the main culprit of the battery drain is but there are several things that have a part. Listing off the top of my head, the radio, the ccu, the ecu, eps and SRS have un-switched power to hold there memory. The Security system and the clock is also active all the time.

Thanks, all that combined makes sense. I guess either a battery disconnect switch or a tender are the only options. Or, driving it daily .

 

[nis350]

I would not get to excited about the battery draining in 4 to 6 weeks. The normal drain of an NSX is 40 to 65 mA. That will drain a perfect battery in about 6 weeks.

The battery does not need to be disconnected when using a charger.

Thanks for the info. I can sleep a bit better now.

Any idea how long it will take the alternator to recharge the battery once I get it started? I read somewhere that the output of the alternator is fairly constant even at idle as long as I am not running anything (radio, headlight etc).

 

[Briank]

Thanks for the info. I can sleep a bit better now.

Any idea how long it will take the alternator to recharge the battery once I get it started? I read somewhere that the output of the alternator is fairly constant even at idle as long as I am not running anything (radio, headlight etc).

20 min to an hour.

 

[ralph cerbone]

just get a battery tender or some other float charger . After the late 80's eletronics in cars had to be powered up for memory , I have seen cars draw as much as 200 m/a (cadillacs with 17 computers in them or bmw's ) Newer cars have memory that go to sleep . I have a optimate charger which i consider to be the best charger made . It just failed last week after 10 yrs ,called company, told me to send it back they will fix it free .Hows that for a guarantee !!!

 

[captngaryr]

I'm with BrianK on this one. Disconnect one of the battery leads and insert a multi-meter on the mA scale and find out what the current draw is. If it's over 65 mA or so, you need to find out where it's going. A battery shouldn't go dead in 2 weeks. if it is over 65 mA, start pulling fuses to isolate where the problem is. Often it's aftermarket equipment (such as alarm systems) that are the culprit. It will take a couple hundred mA to kill a battery in 2 weeks. A trickle charger just covers up a problem that needs to be addressed.

Gary

 

[Nukem]

my battery(brand new) would drain in about 3 - 4 weeks. My 93 Legend was the same way. so I just stick the battery tender on it if I am not going to drive it for awhile.