[darrinsmith]

Hi,
I just came back from another sucessful offroad camping trip with the Cayenne, spoilt only by a flat battery, (due to my son going in and out of the car all the time while parked).
I want to get a solar trickle charger for use when the car is parked up for a week or so.
The local auto shop has several, with either aligator clips and/or cigarette lighter adaptors.
What is the best way to trickle charge the battery? through the aligator clips onto the jump posts under the hood, or via the 12V power outlet sockets in the footwell?
Thanks
DS

[RFM]

The cigarette lighter is the best and easiest way to go IMHO.

[darrinsmith]

Isn't the cigarette lighter switched?
so if the ignition is off, then isn't it isolated from the battery?
so it won't charge at all?
Jump posts sound like the go.
Cheers
DS

[RFM]

Cigarette lighters in all Porsche's should be switched independent key or door lock positions, in other words with the key in your pocket and the doors locked.

[70Sixter]

The lighter in my car is not switched. If it were then a battery maintainer (AC or solar) would not work.

Until I rewired/hardwired the radar detector I had to turn it on/off.

[mmdo1]

I am working overseas and only get to drive my "baby" every couple months. My solution to keep the battery charged was to use an old battery charger with dual mode, 6amp and 2amp, AND an old mechanical timer ((stolen from my wife Christmas tree set up!). I set the charger on low 2amp charge for 5 hours a day. This timing was arbitrary as I have no idea how much battery drain on an idle 997. Clipped directly into the battery terminals in the front trunk as the old charger didn't have a cigarette lighter connection. One issue was the trunk light remained on all time as I could not completely close the trunk with electrical wire hanging out. This could burn out the lamp and or drain the battery further. I resolved this problem by prying out the light assembly (very simple with a screw driver), unclipped the connection, and voila, light off. One unanswered question from me is whether it is harmful to the battery if overcharged. I don't want to face with replacing these expensive batteries every time I come back from overseas.

[wvicary]

Yes it's harmful to the battery to overcharge it. You need to purchase a battery maintainer and not a battery charger.

[darrinsmith]

Ok we went camping again, (these cars are AWESOME offroad - but that's another story).
I connected the solar trickle charger to the power outlet in the rear, and sat the small panel on the roof of the car.
Worked perfectly!
In my car (2003 turbo) the cigarette outlets are switched, so you need to use either of the 12V power outlets in the rear, or the ones in the passenger footwell.
Happy camping!
Darrin Smith
Perth Western Australia