I’m getting ready to leave my 08’ Cayenne GTS sitting for 3-4 weeks again, with the possibility of longer as the war in Ukraine is unpredictable these days.

I bought a Schumacher SP-200 trickle charger which is supposedly a battery maintainer. Here’s my setup, I’ve never done this before, and there’s no negative post on the battery terminal so I clamped it to a random bolt.

Please let me know if this is setup correctly and if I should change anything before I leave the country. Thanks!

-Johnny

 

Correctly clamped. That isn't a bolt, it is the actual negative terminal for jumper cables.

 

some food for thought.
Your battery is a AGM, it requires a SIN wave charge, the charger you have and most cheap stuff out there is a square SIN wave format. The argument is that given enough time on that charger it will damage the life of it but so will no charge but only if the volts go lower than 12.5 to 12.6 (half the batteries charge)
I'm assuming you did this because your not next to an outlet. its better than nothing for short lived durations like a few weeks. The issue is that these cheap units will damage the battery if and when they fail as it just keeps dumping volts into it.
IMO the best case for you is to forget the charger and go start it up once every 2 weeks for 5 minutes.

 

Yes, that hookup is correct.

But if I were leaving it for an undetermined amount of time, I would disconnect the battery instead. No need to lift the driver's seat to do this. You can detach the negative battery cable where it connects to the floor, right in front of the driver's seat. Then lock the door with your mechanical key. No alarm will be running, but no battery drain, and hopefully the battery will survive just sitting disconnected.

 

Interesting - got any good suggestions for a "good" maintainer?

I've got a new properly-sized AGM, and based on the rumors of vampire drains, etc., considering adding a maintainer to be used whenever I'm not driving every few days. I bias towards the wife's mazda for errands and DD duties, so it sometimes sits until this weekend or next...

Thanks for any suggestions!

 

... and for that matter, any good recommendations for a good solar-based maintainer for AGM? I'm thinking I can leave the solar panel on the garage roof most of the time, then take it with me on any overland trips as a backup tender...

 

Anything from Deltran, not cheap but the best IMHO. Anything with a motor and a battery on the property that isn’t driven/used daily, has one. It’ll greatly extend battery health, and life…that has been my personal experience anyway. YMMV

 

the ONLY charger i even bother with now is NOCO GENIUS in whatever you need in amp hour rating. they are AC plug in but you COULD use a 200 watt inverter off the solar cell into a small 12v motorcycle battery to even out the charge then into the NOCO.
BUT trust me when i say it would be WAY better to just unplug the battery. if your going to store it for more than 4 months, take the battery out and charge it in your place with the noco.
i have had dozzens of other brands and various batterys from 6 120ampH deep cycles for my trolling motors to various 12v AGM, and other acid cell batteries for motorcycles and gocarts that sit for years on end with little use.
in the end i have found that ALL the cheap chargers are all built with the same cheap internals and they all fail and when they did they kill what was attached to them. pay up for the NOCO, its a solid state and has MANY features that are good for the battery vs dumping volts.

 

In theory, maybe. In reality? Does your Cayenne's alternator/electrical system charge the AGM battery any differently when the car is running? Didn't think so.
And no, don't start the car every 2 weeks for 5 min - the battery will loose more charge for the startup than it will gain in 5m of running. It takes about 15m of charging to replenish the battery after a startup (to cover the said startup).

Unless you have aftermarket accessories drawing current beyond how the car shipped from the factory, or your battery is on it's last breath as is, leaving the car for a month will be perfectly fine. Charge the battery fully before leaving, and it'll start right up a month later without trickle charger. Charge again afterwards if the car doesn't go back to regular usage.
If you were leaving it to hibernate over the winter, then trickle charger would be needed. 1m is not an issue.

Good luck on your trip!

 

Why Yes it does. Connect that solar charger or any other cheap "charger" into a oscilloscope and then check out the same from the alternator. VERY different.

Another incorrect statement. This is typically correct for those with a battery that had had to be jumped as is lower than 50% charge. The voltage loss over 2 weeks of sitting is so small that 5 minutes of running is MORE than enough.
Again if you have doughts, check out how these cars and how batteries work and check yours with a multimeter. 12.8 to 12.9 is a fully charged battery. go out and you will see in 2 weeks voltage is still where it was, and starting takes about as much charge from the battery as 1 minute of engine running.


OP has the car sitting for 4 months, not 1 month. dissconnecting the battery is best here but basically it should not be a problem like you and all of us have said already.

DUDE. if you have bad information or are not a expert on the topic, do not chime in please.

 

Just for giggles, what does this mean? Solar cells are DC out. I call BS.

 

More food for thought, at least when giving advice on how long a battery will last when just sitting there. It makes a big difference, where the vehicle is parked. If it is alone in your garage or behind a barn far from civilization, it will last longer than when parked in, say an airport car park or a busy store parking place.

The reason for this is that almost every car and truck today has remote controlled locks. There are only a couple of different frequencies the remote controls use and even though I don't know how to explain the technical side of it better, for all intents and purposes it can be described as a kid shouting at a schoolyard "Hey Pete!" everytime someone presses a button on their remote fobs. When that happens, every single remote control receiver in every single car that "hears" this call, wakes up and checks if that shout was meant for them. The one car that identifies as "Pete" will open its central locks and all the other ones will stay locked as they are Frank, Bill and Mary, etc, You get the picture. The problem here is that every time this happens, the control unit in every car or truck has to process that query and that wakes up the canbus and various other control units. It does not take many milliamps but when you multiply that by thousands of times a day, it all adds up.

And that is the reason your battery will go flat faster in some places than other, even when you filter out the obvious temperature conditions.

 

Thanks for the suggestion. Are there are downsides to disconnecting our Cayenne batteries? Things like needing to reprogram the remote, etc.

 

My Cayenne sits on a battery maintainer for months at a time. I use Battery Tender brand maintainers and have one for each car and the 3 dirbike motorcycles that have electirc start. Every car except the 2 DDs sit on a maintainer whenever they're parked in the garage and I leave them unlocked. I've gotten 12 years from an AGM battery in one and regularly 8 years from others. All the cars and bikes have AGM batteries.

 

I'd like to know what kind of scope he has that detects SIN waves. Both of my Agilents detect sine waves. lol

This coming from a DUDE who thinks an engine may be salvageable after finding piles of metal shavings in an oil filter. The same DUDE who thinks his Cayenne has 3 transfer cases.