HOWTO: Permanently Connect Battery Maintainer Terminals
Written by Wild Weasel
This is meant for 991 911 owners who want to make it easy to hook up a battery maintainer
when they won't be driving their car for a few weeks or months at a time.
Skip to the Details.
Plenty of people ask about which 12 volt outlet they should plug their battery maintainers
into. Some of them will stay live only if they detect a maintainer plugged in while
others will turn off a few minutes after the car is turned off no matter what.
Even the ones that stay live can go dormant if you have a power outage and it no
longer detects the current for a while. When the power comes back on they may not
go active again and you could be left with a dead battery you weren't expecting.
With the electronic frunk release on these cars, this can leave you with a real
hassle trying to get things back up and running again.
So here's my solution. CTEK makes a connector to permanently attach to your battery
terminals with a quick-disconnect plug on it that attaches to their chargers.
You may be questioning the installation as everyone knows you're not supposed to
connect your charger directly to the negative battery terminal. Trust in me. I've
done the research and the reasoning behind this is a cautionary tale from many years
back when batteries could produce explosive gases and connecting to the terminal
directly on the battery could cause an explosion. That led to laws and regulations
that still make it a legal issue today for companies to instruct people to connect
directly to the negative terminal.
I assure you this is perfectly safe and works exactly as you want it to.
Here are the Details
Firstly, it goes without saying that you should not try to drive the car with your battery maintainer connected. A few people mentioned this
as a mistake they've made and suggested putting a piece of paper under the windshield wiper or on the dash saying "Battery Maintainer Connected"
so you don't accidentally forget about it and drag it along beside your car.
The two key details I want to show here are where to connect the terminals, and
how to hide the cable and connector when you're not using it.
As you can see in the pictures, the red and black terminals are attached directly
to the battery terminals. It's as simple as that.
Then, in order to not have the cable dangling around in there when it's not being
used, notice that you can tuck it perfectly into the little box that holds the tire
inflator. There's a gap under the lid at the back so you can run the wire without
pinching it and space beside the inflator to tuck it in safely.
When you want to use it just take out the connector, run it under the gap by the
windshield, and plug in your charger.
One last thing worth mentioning is that I used to put a towel over the fender of
my Boxster out of paranoia about potential marks on the paint. In this case, there's
a PPF wrap on the car so I'm not concerned about the wire lying across it.
That's all there is to it!