Leaving battery tender connected while on vacation?

My 2009 has been hooked up to a tender for the last 3 years. The only time it hasn’t been, is when I’m driving it. I’ve got 10 toys hooked up to tenders full time. Harley, golf cart, track car, wife’s SL55, etc.

 

Yes ! That is when you need it most

 

Counter argument: if it makes you more comfortable on holiday ensure the car is fully charged just before you leave - turn charger off and then as soon as you return turn it back on - I suspect ten days will not fully discharge or damage the battery but check it anyway (even just using charger lights) rather than start the car until sure it is fully charged again - worst case 430 battery is relatively cheap easy to buy and change yourself

 

It’s no problem at all!! That’s what it does.

 

All my cars always left on for weeks at a time

id only trust ctek

 

I leave the 458 plugged in for 6 weeks while I’m in Florida.

 

Most chargers, I recommend CTEK, have computers in them that constantly read charge levels in the batteries and stop charging once the battery is fully charge and then turn back on once the battery has discharged to a certain level. They are perfectly safe and the technology has been around a long time and is well vetted. The 430's immobilizer is a parasitic drain on the car and in my 430, I no longer own, the immobilizer is rather quick in discharging a battery vs. leaving the immobilizer off. Leave the car on tender.

 

I leave it uplugged, one less thing to worry about

 

Yes, I have a CTEK 5.0 and that 8th stage is when it pauses the charging to let the battery discharge a bit and then recharges it back to 100% in 7th stage. I notice it takes almost a week for that to happen on my car I rarely drive...not sure how often others have it in that final stage.

 

Sounds like you may need a new battery. My typical recharge time is less than 30 mins. on my CTEK Multi US 7002.

 

My car has two batteries. One is brand new and the other a year old. It takes 30 minutes or less to get to 100% charge (float, stage 7) after driving it a short distance and reconnecting. It's the stage 8 (pulse) where it stops charging the battery and lets it discharge I notice doesn't happen for a week after it has been on stage 7. So my battery is sitting at 100% fully charged before the CTEK lets it discharge to 95% or whatever in stage 8 (pulse).

 

That is normal ...it can take up to 10.days that restarts every time you unplug it

 

Unplug it. I have been saying it for years and two nights ago my friend lost 6 cars likely likely likely due to a factory issued charger.

 

Not sure if directly from the charger or maybe indirectly. Charging a battery releases hydrogen gas and if not ventilated correctly can ignite. That's why batteries (most) need a vent tube attached to them when installing to ensure the hydrogen gas can escape if in an enclosed space like trunk or footwell. Batteries already in an open area like under the hood don't need to be usually, but I guess should somehow if recharged when not driving as moving air would ventilate the engine bay...

 

Alternately, since the F430 is of an old generation that offers this possibility, disconnect the battery with the so-called master switch.
There is some procedure to follow when switching it back on, but it will prevent all issues with parasitic draw or battery tender.
On my 599 (which is from the same timeframe as the F430) I always did that and never got any problem.
On the other hand, my 488 has the tender plugged permanently when parked (even for long periods of time) and it never caused any problem either.

 

Some chargers can draw current from the battery if left connected to the battery with the AC disconnected from the charger.

 

All my cars and motorcycles are on tenders (none are CTEK) full time, here at the house or away. When we travel to Europe once a year, our two daily drivers have tenders on them also.
Been doing this for many years (25+) and never had a problem.
When I worked and lived overseas, the cars had them for 6 months at a time. Again, no problems encountered.

 

He'll need the radio code if using the kill switch.

 

I've got 5 cars that I put away for winter storage and they're on tenders continuously for nearly 6 months. Done it that way for many, many years with never any problems.
That's what they're for.

 

Mark me down as another “full time tender” person. My 430 is in the Ctek tender whenever I’m not driving it.

 

I hope your luck continues. My buddy here in az literally lost a couple million bucks in cars and almost everything. He happened to be there when the car went up in flames.

 

With that much lost to flames, I'm surprised he didn't have a fire suppression system.

 

It's a large warehouse.

Luckily the sprinklers didn't go off and ruin everything else in there.

 

I am also just too paranoid to keep tenders hooked up all the time. I seem to do fine charging cars for a day or so (until the tender indicates full charge) and then uplugging them. At that point they are ready for use, or to go another week or two until they need to be charged again. The other benefit to doing things this way is you get a feel for how long each car should take to come up to a state of full charge. When things start to take longer it's an early warning sign that the battery needs to be replaced.

IMHO the real problem with these cars is low voltage STARTS. That is what causes all of the errors. Mildly low voltage during storage doesn't seem to hurt anything, assuming you never let a battery become really discharged to the point where ECUs, etc. loose their settings, and bring them up to full charge before starting.