Battery Tenders

[The Stig]

Since I'm traveling for two and three weeks at a time lately, It's near impossible to keep the battery charged enough the be able to crank the engine when I'm back home. That little voice inside my head is telling me that letting this thing drain down for 2 or 3 weeks, and then jumping so I can let it run to help charge the battery back up, may not be a good thing for the battery...

I have a heavy duty charger and Jump, but I was wondering whether or not it makes sense to buy a decent battery Tender or Trickle Charger as well.

How long can you realistically let it stay connected to the Tender?

What are your thoughts? What would be your picks for the better tenders?

Thanks,

[kbentzel]

I've been running Battery Minders on my red top Optimas for years. I haven't had a battery failure and the cars are always ready to start. ON the GTM with Isis the battery is dead in 4 days without it.
Keith

[VRaptor SpeedWorks, LLC]

It is important to keep all of your loads in mind BEFORE you wire up your car, so you don't have to deal with this problem. If you're running ISIS without the inReserve set-up (which I would like to take credit for pushing into existence ), you're missing the boat. Wire up the solenoid so that it cuts power to EVERYTHING except the stereo memory and ECU memory. With just those 2 things hooked up, you should literally be able to leave your car set for months on end with no drain on the battery.

Another note on the inReserve.......make sure you put your "over-ride" solenoid button somewhere easily accessible on the exterior of the car (I put mine in the top louver of my side-scoop louvers on the driver's side, so I can easily reach into the side scoop area and hit the button). DO NOT let the inReserve trip the solenoid every time, as it will drain the battery down to about 60% before it trips out. Instead, trip in manually with the switch every time you know you are leaving the car for anthing more than a few hours.

[The Stig]

I've been running Battery Minders on my red top Optimas for years. I haven't had a battery failure and the cars are always ready to start. ON the GTM with Isis the battery is dead in 4 days without it.
Keith

I don't have the ISIS system, but I do have a Push Start system with an Alarm System built in, that seems to be the culprit. I think mine is good for about a week and then it's questionable.

What Minder do you use?

[kabacj]

It is important to keep all of your loads in mind BEFORE you wire up your car, so you don't have to deal with this problem. If you're running ISIS without the inReserve set-up (which I would like to take credit for pushing into existence ), you're missing the boat. Wire up the solenoid so that it cuts power to EVERYTHING except the stereo memory and ECU memory. With just those 2 things hooked up, you should literally be able to leave your car set for months .

Great tip Shane. I was almost ready to bag the Isis idea.

John



John

[mmaragos]

I use a Battery Tender brand, one for motorcycle, one for the GTM. These have been good to me for about five years now. Other option would be a manual disconnect (although you want the PCM and radio to have constant power like Shane indicated).

[65 Cobra Dude]

Shane,

Can you tell me more about the inReserve setup? I went to Isis' website and all it has is a picture, no details. How hard to install in a complete car? How it's hooked up, etc... Anything you can tell me will help. It ticks me off that I fell for this great system only to have it kill my battery.

Thx,

Henry

[VRaptor SpeedWorks, LLC]

Not to de-rail the thread, but to answer Henry's question:

You need to have ISIS program one of the powercell outputs to trigger the inReserve solenoid. ISIS monitors the batt voltage and when it gets down to 12.2, it sends an output to the solenoid, which trips it to open up. This solenoid is unique in that every time you send voltage to the trigger it switches between off and on......think ball-point pen....every time you push the button...ink out, ink in, ink out...... So you have the ISIS output triggering the solenoid, and also a momentary switch wired to the same post on the solenoid. Every time you push the button on the switch.....solenoid on, solenoid off, solenoid on, etc. When used together with their inLink remote key fob, you can arm the car, which arms the security and will not let the car start, then push the button on the switch to kill the inReserve solenoid. This shuts power down to the whole car. ISIS will remember that the security was enabled BEFORE power was killed to the system, so even if someone knows where your inReserve switch is, it won't matter.....all it will do is fire up the ISIS system, (security still enabled) and if left alone, ISIS will trip the inreserve solenoid again when volatge gets down to 12.2.

So all I have wired up to the + battery is the heavy cable back to the starter (where I also pick up power for the ECU memory), stereo memory and a cable to the inReserve solenoid. That's it. Everything else is wired in on the other side of the inReserve solenoid. This also takes care of the problem with the power window switch illumination.

This really is how the whole inReserve came about. I pretty much told ISIS I would not buy a system without it as I knew the battery would only last about 3 days....4 tops and have enough power to start the car. Now, you hit the "lock" button on the remote to arm the security, push the momentary inReserve switch to power the whole car down and walk away for weeks....months.....whatever. No battery tender needed.

[65 Cobra Dude]

Thank you Shane. I especially like the ball-point pen analogy. Makes it simple to understand.

Sorry about the thread hi-jack Stig. Now back to regular programming. I use Battery Tender brand as well and leave my spec connected to it all Winter inside a tent. Keeps the battery fresh even when the temperature drops.

Henry

[crash]

I use battery minder, and small solar panels on things that are outside. (Trailer, tractors,etc.)

[Marty Prario]

I use CTEk charger/maintainer/conditioner. The best units on the market.

[The Stig]

Thank you Shane. I especially like the ball-point pen analogy. Makes it simple to understand.

Sorry about the thread hi-jack Stig. Now back to regular programming. I use Battery Tender brand as well and leave my spec connected to it all Winter inside a tent. Keeps the battery fresh even when the temperature drops.

Henry

Don't worry about it Henry. It was good info.

You also answered one of the questions that I still had; How long can you leave the tender on without worrying about batter over-charge / meltdown. Lately, I've been traveling for a couple of weeks at a time. By the time I get back, the battery is too low to start the car.

It sounds like I can just leave it hooked up and charging until I get back without needing to worry too much.

I use CTEk charger/maintainer/conditioner. The best units on the market.

Thanks Marty. I took a look at the web-site. Fairly Pricey, but impressive. I think I'll look into picking one up this weekend.

[eseethal]

Yes, I have 2 of them, not very cheap, but they really extend the battery life, and you can leave them attached for longer periods.

I use CTEk charger/maintainer/conditioner. The best units on the market.

[jdpanero]

I just wired a cutoff switch like this directly to the battery ground:

http://www.amazon.com/gp/product/B00...STQF1FASMCFQVR

I've had the same red top Optima for 4 years and it will fire after a month of sitting.

[The Stig]

I just wired a cutoff switch like this directly to the battery ground:

http://www.amazon.com/gp/product/B00...STQF1FASMCFQVR

I've had the same red top Optima for 4 years and it will fire after a month of sitting.

Thanks JD. How's that Beautiful Red GTM treating you?

[The Stig]

I decided to go with the CTEK (7002) charger / maintainer / conditioner...

I never new that car batteries could be re-conditioned. (But apparently they can).

Thanks Marty!

J.D., I really like the idea of the cut off switch that you sent the link for. I may be doing that as well. Does that allow you to cut the battery but still maintain power to the ECU?

Mike

[docglock]

I have a Porsche battery maintainer that I can plug into the wall and into the hot 12v plug on my Corvette and Boxster. It works great when these cars are in storage (months at a time). My build plan includes the ISIS system and the InReserve module. I also want to have 12v hot plug for my battery maintainer. Am I looking at this too simply? Is there something I am not considering with this kind of set up?

I do appreciate Shane's insight on where to place the override switch.

Thanks!

[fact5racer]

Man, I sure wished I had used the ISIS sytem so I would have to keep plugging and unpluging a charger on to my car. It sucks going 4 months and then getting in to my GTM only to discover my battery is still fully charged. Maybe we could start a fund called "Buy Gary an ISIS system so he doesn't feel alone"?

[narkosys]

Interesting, so what is causing such a quick drain in the battery? I am sure that if I leave my truck alone for several days it will start, so what is so different on the GTM that it will suck back a battery faster than an iPhone?

I am enjoying this thread as I am thinking of installing the ISIS system and am getting some good information out of it.

P

[Timbob From Texas]

I am a factory sales rep for Schumacher Battery Chargers, and there are some things going on in the battery/battery charger segment that most of the public isn't aware of. Around half of the new cars being sold today have AGM (absorbent glass mat) batteries in them - there is no liquid acid in them (an Optima battery is a good example of an AGM battery). There are several reasons for this, but the 2 biggest reasons are this is a better battery design that will hold up under modern vehicle electrical demands, and the OEM's don't have to deal with liquid acid in their warehouses or on the assembly line (less hazmat issues). Bottom line is this - if you use the same battery charger you've had for the past 7 years or more, you will actually degrade and possibly cook an AGM battery. New technology battery chargers will have verbiage that says something like "Speed-Charge", "Smart-Charge", "Microprocessor Controlled", or something similar which means they pulse charge instead of just dumping amps into the battery. You MUST have one of these chargers to properly charge an AGM battery. The good news? These new chargers charge the traditional lead-acid (liquid acid) batteries faster and more complete than the old technology variety. A good battery maintainer with this new technology in an automatic mode will NEVER degrade or cook a battery - they are totally safe to plug in and leave for days/weeks/months at a time without any worries. They will keep your battery fresh and ready to go whenever you need it. Here are a couple of links to examples of these battery maintainers:
http://www.batterychargers.com/Produ...tName=94026849
http://www.batterychargers.com/Produ...Name=940261074

If anyone wants more information, e-mail your requests to me at [email protected]

By the way, I am hoping to build an MK4 sometime in the future. Already collecting "stuff" for the build.