MikeekiM

Ugh... I have my S2K on a Battery Tender most of the year...

Over the weekend, I took it off the tender and went to start it, and my battery was completely dead... Not even the typical audible clicking sound when the battery is too low to turn the car over...

Apparently, the 7.5A fuse on my Battery Tender blew at some point, and hasn't actually been trickle charging...

I don't have a proper charger, so I put it back on the Battery Charger and once the battery is strong enough to start the engine, I'll drive it around and let the alternator charge up the battery...

This Interstate battery is less than one year old...and it has only been drawn down to zero this one time... Do you think this battery is still serviceable? Or should I consider replacing it?

Thanks all!

engifineer

I am more concerned why it died and why your tender popped a fuse. How long since you know it was charging or last driven? It should be able to sit a good while and still start.

sam_spider

I've brought a battery back from the dead with my normal charger before, haven't tried it with the trickle charger before, but it should be able to charge it. I didn't have any issues with the battery when that has happened, at least none that I'm aware of.

Agree with the above though, need to find out why the fuse blew on the charger.

MikeekiM

I bet it's been 2-3 months since I last drove my S2000. Unfortunately, I do not keep driving records at that level of detail. As a result, I don't know when the fuse was blown... I know that we had a couple of short power outages during last week's heatwave, and the surge from the service restoral could have blown it...but a week off the tender wouldn't explain the dead battery.

Bringing a battery back to life with a trickle charger is pretty difficult... I am not sure it's going to work, but that's all I can do in the short run... I didn't have any spare 7.5A fuses, so I threw in a 5A fuse for now. Hopefully it won't blow... As I mentioned, I haven't driven the car in 2-3 months, so perhaps being on the trickle charge for a few weeks will restore the battery enough to at least get it to start, and then I can drive it around to let the alternator work its magic...

engifineer

Have you measured the actual voltage of the battery without it charging?

Car Analogy

I've recharged fully dead batteries with my Battery Tender many times. Takes a while, but works. Its way better for batteries future lifespan to trickle charge it back to life than to charge it with alternator.

The one gotcha is getting tender to recognize its connected to battery and even start charging it. Tender senses voltage, so it doesn't do anything unless it senses a battery. That is why its ok to short tender cables together and not spark.

So to get tender going, you need to trick into starting. A simple 9v battery will work. Get a 9v harness, and some alligator clips. Make sure red gator goes to harness + and black to -.

Whenever you got a dead battery, connect harness alligator clips to tender gators. Red to red, black to black. Connect tender to car battery. Now briefly connect 9v to harness, until tender charging light goes on. Remove 9v. Let tender do its work.

MikeekiM

I have not. I don't have the tools/means to do it myself...

baldspot_lol

a good time to order a multimeter then! you can get one for like 5-10 bucks, and can learn the basics of using one in a 10 min youtube video.

but more than that, i'm not fond of leaving any electronics alone. a charger that blows fuses that by design i have to leave unnatended for days / weeks? going straight in the bin.

edit: when i bought my s2k, the owner had left it for 6 months and battery was dead. i could rub a baloon on my head and give more current. still working fine 10k miles and a year later after being jumped for the test drive

cosmomiller

It has been my experience that once a battery has been run down to zero, it will not have the longevity and performance overall that a former “undepleted” battery would. You can bring it back and with regular driving and/or external charging/trickle/minding it will start and keep things going but it will not last as long. It will be easier for the run down battery to develop a short and run down much sooner.

Car Analogy

Quite true. But you can still potentially get years of service out of it. Can always carry one of those jump start boxes around with you just in case there is an issue.

Not that I'd buy one just for that, better to put that towards a new battery. But if you already have one or want one, then just carry it vs sitting on shelf.