Battery Disconnect Questions

[rochguy2000]

Hi Guys,

This is my first winter with NSX. Although I have put the NSX in the storage in the beginning of November, I have not disconnected the battery yet. I waas looking for a a kind of trickle charger which you could charge at home and take it to NSX in storage which in turn will maintain the battery. Looks like the one like that does not exist. The storage does not have access to electricity, so I was starting the car for 20 mins when the weather was good and taking it for a drive to keep the battery charged. I would like to disconnect the battery but would like to know if we need to enter any code through the radio when the battery is re-connected? I do not have stock radio anymore.

Also would it be sufficient to remove negative terminal or would you guys recomment taking both the terminals out and taking battery out?

Typically how much time does it take for ECU to learn new settings to bring back the idle to smooth levels after the battery is reconnected?

Would it be a good idea to keep the battery in and start the car for 20 mins every weekend? I would not be able to take it out though given the season and salt on the road.

Any information is appreciated.

TIA Rishi

 

[Larry Bastanza]

If your storage area does not have access to power for a trickle charger I would recommend you completely remove the battery. Batteries do not like being stored in the cold. (I assume no electricity means no heat either). Store the battery in a dry place preferably at room temp. Also if it is cinnected in is powering the alarm system. The obviously has its' down side too, in that the alarm will be disabled if the battery is disconnected.

My NSX is on a trickle charger in a heated garage, so I do not have this concern, but my lawn tractor is out in the cold. I completely remove the battery and store in in the heated garage. This battery although quoted at a 2 year life, has been around for 4 years with no issues. I am sure if it was out in the sub-freezing temps in the NE all winter it would be dead by now.

HTH,
LarryB

 

[sptrader]

NEVER leave a trickle charger on a battery for long periods of time, what you need is a "Battery Tender", they are designed for that purpose.
They are available as cheap as $10 from Harbor Freight or about $60 for a fancy one from Griots .
I've kept one on each of my Summer cars all Winter with no problems for many years now.
(Trickle chargers have been known to blow the top off of sealed batteries and spray acid everywhere !)

 

[rochguy2000]

If your storage area does not have access to power for a trickle charger I would recommend you completely remove the battery. Batteries do not like being stored in the cold. (I assume no electricity means no heat either). Store the battery in a dry place preferably at room temp. Also if it is cinnected in is powering the alarm system. The obviously has its' down side too, in that the alarm will be disabled if the battery is disconnected.

My NSX is on a trickle charger in a heated garage, so I do not have this concern, but my lawn tractor is out in the cold. I completely remove the battery and store in in the heated garage. This battery although quoted at a 2 year life, has been around for 4 years with no issues. I am sure if it was out in the sub-freezing temps in the NE all winter it would be dead by now.

HTH,
LarryB

Thanks a TON Larry! and to you too SPTRADER. I have a question though regarding how much time does it takes for CPU to learn new settings once we install back battery? Also do we need to know any code to enable immobilizer system? come to think of it; there was none in 94 NSX right? Help me if you can. Today I went to storage and kept the NSX running for 20 mins. At cold it was showing the charge between 10-11 on battery monitor. after it is showing charge between 12-13. Is running it every 2 weeks for 20 mins a good option?

 

[Briank]

Is running it every 2 weeks for 20 mins a good option?

In my opinion no, pull the battery and let it sit.

 

[Malibu Rapper]

See this thread. I concur with BrianK. Schumacher also has a new device that you can buy at Walmart for maintaining batteries and it's only about $20 and it acts like the Battery Tender. We'll see how my xB2 like sitting for a month with it hooked up as I'm in Bangkok now. The quality of the unit is not up there with the Battery Tender Plus that I have as you can tell immediately when you handle the connectors. But if it does what it says, it should do the trick.

I bought one of the Harbor Freight units a few years ago and went on a 3 week trip and came back to find the piece of crap broke and my battery was dead. It did something real bad to my battery as it wouldn't charge correctly until I finally did a desulfization charge with a Vector charger. I would say spend the extra $10 on the cheap Schumacher or if you want one that will last you a long time and is high quality get the Battery Tender Junior or Plus. I've installed them for others and we all love them, car starts up like it the battery was brand new every time!

 

[OLDMNSX]

I have a question though regarding how much time does it takes for CPU to learn new settings once we install back battery?

I was not aware of our CPU retaining any driver style inputs. I know that my daughters 01 Lexus is300 does this, but not our NSXs. Clue me in.

Today I went to storage and kept the NSX running for 20 mins. At cold it was showing the charge between 10-11 on battery monitor. after it is showing charge between 12-13. Is running it every 2 weeks for 20 mins a good option?

The voltage indicator on the dash shows battery voltage when the engine is not running. With the engine running it shows the voltage that is in the electircal system, i.e. the alternator input to the electrical system. With the engine running at 1K RPMs or greater the voltage should be between 13 to 14 volts. It takes a little over 1 volt to get the flow of electricity to reverse course back into the battery and recharge the battery.

Is running it every 2 weeks for 20 mins a good option?

NO, that is the short of it.............I don't like to use NO, so read on.

Now, the long of it. When you do this the entire engine and exhaust system does not come up to a high enough temperature, for long enough, to evaporate all of the water vapor that is produced by running the engine. Just a little history of internal compustion engines. Water vapor is a by product of the internal combustion engine. This moisture also gets into the oil, so if the oil doesn't warm enough to expel the water it sits in the oil and causes problems there with the bare steel parts on the interior of the engine.

The water also sits in the exhaust system and causes problems there in most cars. The NSX stock exhaust system is mostly stainless steel that is pretty much impervous to water.

Do you ever wonder why cars during the winter time, around 40F or lower, look like they have steam coming out of the exhaust? This is the stuff I am talking about. Or have you seen water dripping out of the exhaust, or wonder why a car that gets driven on short hops needs its muffler replaced every couple years, but one that gets driven for at least 30 mins, has the original muffler for 100K?

Well, you asked,
Brad

 

[L8apex32]

In my opinion no, pull the battery and let it sit.

Yep. Just take the battery with you. That's standard practice for long term storage.

The ECU will learn what it needs to know quick enough that it won't affect your enjoyment of the car next spring. No worries.

 

[rochguy2000]

Thanks guys! took the battery home today alongwith spare tire; tire support and battery holding bucket and battery holder so I can clean everything and will put back in spring..Man taking that battery holder out took me so long