Porsche Battery Tender

[Bertever991]

I use the socket inside the center console of my MY15 991.1. It works. I tried to use ring connectors but the battery bolts seemed to be peaned so the nuts won’t com off. I don’t think spade connectors work well because they tend to spread when tightened. Do you just force the nut off the battery connectors?

[Eli992]

When connecting directly to the battery, why connect the negative to a ground rather than direct to the battery?

[Tom]

When connecting directly to the battery, why connect the negative to a ground rather than direct to the battery?

For lead-acid batteries, there is a risk of the battery clamps sparking when you hook it up to the battery, which can ignite the battery's out-gassing and explode. So it you hook up the ground away from the battery, the spark will be less likely to blow up the battery. They also claim that the current can get to the starter motor easier with the good battery hooked up to the chassis, rather than hooking it up to the battery post where it needs to travel through a single ground strap to the chassis -- though that might be a bit academic if your cables are in good shape.

[audi4t]

When connecting directly to the battery, why connect the negative to a ground rather than direct to the battery?

Modern Porsches have an electronic module in series with the -ve battery lead integrated in the terminal connector.
This monitors charge and discharge current which is recorded in the cars battery monitoring memory and used for controlling alternator charging parameters.

If you connect a charger directly to the -ve terminal of the battery you are bypassing the monitoring system and potentially messing with the cars alternator charging settings.

[Stigs cousin]

For what it's worth I had this discussion with Gunter Feldmeier at Fremont Porsche( he was the service manager there) about a year ago when I was in getting a battery installed and the battery error message reset.I got about 6 years out of the battery in my 2016 GT-4.Since I had bought the car as the 2nd owner I had been using the cigarette lighter socket with a Porsche branded tender which looks identical to the CTEK one, by the way.My questions to Gunter was is this the typical life of a battery now day's? He said, "6 years is a long time for a battery now day's".He also said if the car was sitting for weeks that the tender was the way to go using the lighter socket and be sure to lock the car which puts the car in "Sleep Mode" and battery drainage is at a min. and by locking the car also keeps the tender from "Timing Out" of shutting off.

He also said to drive the car more!

I think one of the issues of charging directly to the battery is weather you can route the cord so your able to completely close the frunk hatch and lock the car so it's in sleep mode.I suppose you could route the cord so comes out near the wiper blades?The lighter plug is very easy to use and the tender is on the passenger seat so you can see any of the charging lights in case there is an issue.

Stig

[cassius]

Hey Stig,
How do you route the power cord to the tender? Open window?

[Stigs cousin]

Yes, I crack the window about an inch and run the cord through the opening.I have a towel to sort of separate the cord from touching the paint (see anal retentive).It's parked in the garage with the cover on it.

Stig

[Racedoc]

I route my charger cables out the door bottoms. There always seems to be enough gap and cushioning from the weather stripping. The 991.2 turboS goes from the cig lighter out the passenger door. The Ferrari 458 goes out the passenger door; the California goes out the trunk. All doors and trunk lid close without pinching or paint rubbing. Ferrari factory suggests this.

[Rich_911]

I also run my cable out from the bottom of the driver's door. The trickle charger connects in the center console of my 997 to the cigarette lighter socket. Works great, no issues.

[rchaas]

The Porsche branded charger is made by CTEK and they make a pigtail cable with ring connectors so it can be mounted permanently. It should fit the porsche branded charger as well. Mine sits in the trough of the left grab hole on the frunk cover that covers the battery/master cylinder/etc. My charger connects to that pigtail and works great.

This is one example, there are others, longer/shorter/smaller and larger ring connectors.

https://www.amazon.com/CTEK-56-382-Comf ... 00&sr=8-14