rbaron

I’ve owned and driven various Porsches since the sixties. In 1988 I visited the factory to pick up my special order 928. Then as needs changed I had several Cayennes and then some Audi Q5s.

Now I have acquired a 2017 Macan Base and having passed 80 (years, not MPH) I don’t drive it all that much.

In about 1988 I bought the battery maintainer pictured below for use with my 928. There seems to be some confusion so I’d like current (no pun intended) advice on whether and how often I should use it now with my Macan, which is kept in a detached garage, neither heated nor air conditioned here in Oklahoma.

TIA,

—Bob

rdubu

I have one of those battery maintainers, but it unfortunately can’t be used with the Macan’s AGM battery. I don’t know anything about the AGM battery tech, but it requires a maintainer that has an AGM mode.

Porsche dictates the use of a maintainer if the Macan is driven less than 6k miles a year. Long time owners may be able to better comment on how frequently to use it.

Spyder Bite

Time to upgrade the battery maintainer

CTEK - 40-206 MXS 5.0 Fully...

rbaron

Unfortunately I drive well under 6k a year; last calendar year I drove my Audi just under 2k.

It's turned out to be true that after retirement we drive mainly to and from medical appointments.

<sigh>

Thanks,

--Bob

Hwy

The CTEK as Spider Bite recommended gets my vote as well.

rbaron

Amazon sure does seem to sell a lot of them!

I would not be in favor of a device that must be hooked to the battery but browsing Amazon I see the CTEK 56-870 which is alleged to work through the cigarette lighter. It has some glowing reviews and I wonder if anyone here has and uses one.

--Bob

BMinSFL

There's a separate accessory that you can connect for a charge through the interior 12v power outlet.

DBH

I'd also suggest a new battery maintainer. I've had very good experience with my Battery Tender brand maintainer. It's less expensive than a CTEK and works just as well.
BTW, the Porsche branded maintainer is just a CETK. But why pay the Porsche "tax"??

DHL

I use a full on battery charger capable of 20 amps. The "maintainers" have typically much lower current capabilities, between 1 and 5 amps. My charger also has a current readout which is very informative for showing how much draw your battery/system is using while under charge.
For example, when driving my 22 Macan GTS 5 miles to the store, after stopping with the motor off, the car will draw upwards of 20 amps for three or 4 minutes then taper down to under 1 amp in the next 30 minutes. It will remain under 1 amp indefinitely if locked. If I open a door the current draw will jump to 8 or 9 amps again for a few minutes as the car "wakes up". If I turn the ignition on (not start) with all the dash lights on, the car draws 18-20 amps continuously.

Charger also has settings for a number of battery types including Lithium, Flooded, AGM, Maintenance Free (liquid) and is fan cooled at higher current outputs.

https://www.promariner.com/en/p/63120/ProNautic-1220P

MarkinMD

I replaced that exact same Porsche Charge-o-mat (that died after 15 years of service) with a CTEK MUS 4.3 charger several years ago. I attach it using the clamps that were included with the charger to the "jumper pins" under the hood.

I wrote to CTEK customer service asking about the correct charge setting for that charger. They responded as follows -
"The normal “car mode” will produce a 14.4V bulk charge voltage that is acceptable for some AGM batteries. The “snowflake” or “AGM” mode will produce a 14.7V bulk charge voltage that many AGM batteries recommend."

When I sent a recommended charging graph of the Varta battery in my 2018 Macan, CTEK responded -
"Based on that graph, you should use the snowflake mode."

However, when I called Interstate Battery about their AGM battery in my 911, they said use the "car mode" 14.4 setting.

schnell

Based a lot of years (30+) of Porsche ownership, with none of the cars daily drivers, I put the vehicle on the battery maintainer whenever it goes in the garage. A few times I might have decided to skip the step as I planned to drive it again the next day, but then something comes up and a week later I notice that it is not on the maintainer, so now I just hook it up regardless.

BTW, I have the Porsche Charge-o-mat wall mounted so it is visible whenever I have occasion to look into the garage from the house. Sometimes with the Macan a power disruption may knock the charge cycle offline (I use the cigar lighter connection method), so it is good to notice if the maintainer's lights are not what I expect to see.

I can say that in addition to the obvious benefit of never encountering a flat battery, I have had to buy very few new batteries over the years. They really last a long time if kept topped up.

rasetsu

That is what I used on both my Macan and my Cayman.

schnell

As you can read in other threads on this popular subject, the cigarette lighter port on the console will disable itself after some time (15 minutes?) unless it senses current flow through the port. So as long as you connect the charger within a few minutes of turning the key on and off, it will stay enabled. As this is clearly a software-based function, I would look for a confirmation that it works in the model year you have (mine is a 2021 GTS).

VAGfan

There really isnt much difference between an AGM battery versus flooded cell.....either charger will work fine on either type of battery, nobody is going to notice the 2% undercharge or 2% overcharge.......

ByByBMW

I agree with what most of the folks have recommended. A Ctek with AGM mode. In the heat and the cold all batteries will suffer. I also drive only 5-7K miles a year and keep my cars on a Ctek if I anticipate more than one day between drives.