mgordon18

Since my recent battery failure, I'm looking for possible reasons why my 1-year-old battery might have prematurely given up the ghost.

One thing I noticed was that when I get out of the car and close the door behind me, the cabin lights remain lit (above the rear view mirror and on the bottom corner of the doors) until I lock the doors, setting the alarm.

Is this normal behavior? If so, how long do the lights stay on if the car isn't locked? I don't do this often in practice, but if I do, I want to make sure I'm not draining a good battery for no reason.

GSIRM3

Yep, that is normal. Mine stay on for about 2 minutes, which is longer than most cars I have owned, but they do turn off.

McCulla

I have a time monitoring disability I think, but mine stay on for it seems like 4 minutes. They do go out.

SARGEPUG

Your in the horrible NE like me, so I assume during the winter you rarely drive it, if at all? As we all know, when the car is stationary, the battery is always being drawed upon by the alarm system, clocks, etc. If you don't trickle charge it during the winter, she will always go dead. Same in fair weather, if it sits for a very long time.

ecostellodo

If you have sport chrono, you should be able to change the cabin light time.

mgordon18

I do drive all winter, although for much fewer miles. I rarely go on longer drives in Winter - mostly back and forth to my son's school and errands. I guess that could do it.

Thanks - I'll definitely try that...

USMC_DS1

A battery should not fail after only a year. What are the symptoms which you're dealing with... is the car not starting up (difficulty turning over) or is the battery drained.

For battery drained symptoms:
Some aftermarket accessories will continue to drain the battery depending on where it's drawing power from until the vehicle is actively locked and/or... the vehicle will automatically shut down accessory power after 2 hours. That's long enough for certain devices to drain the battery. For example, a RADAR detector that is left on for two hours along with a vehicle black box video recorder could drain the battery substantially... then you go out to your garage to open the door temporarily to retrieve something you forgot in the car. This would reactivate accessory power for another 2 hours of draining potentially each time you do this unless the car is actively locked. I've gone to leaving my car on a trickle charger as a force of habit everyday. I don't think about these concerns any longer.

If the battery is not drained but the car has difficulty turning over:
- the battery ground strap on the body side may be loose. Insure that the bolt is torque to 11 ft-lb.

If the battery is drained and the car doesn't seem to be charging on it's own:
- I recall that some forum members have reported an issue with their battery to alternator wiring harness. This requires replacement of the harness to resolve.

Gripster

If you don't drive the car everyday then get a trickle charger. The OEM Porsche version is pretty easy to use since it plugs in via the cigarette lighter socket instead of having to futz with the battery each time.

http://www.suncoastparts.com/product...9972electronic

mattyf

I remember the dealer recommending keeping the car locked when not in use. Stating when unlocked there was a higher drain on the battery. Also I believe there is a sleep mode the car goes into after a certain amount of time to save battery. Not sure if it goes into sleep mode when unlocked.

Leader

I went through the manual last night and couldn't find a way to reduce the cabin-light-time...even via PCM.

mgordon18

There's a menu under "Individual settings" that says, "light fade out time" or something close to that. I set it to 10 seconds, but it didn't change the cabin lights, so that's not the proper feature...

ecostellodo

I guess I'll have to RTFM

ecostellodo

From the manual only the orientation light settings can be changed.

The lights are switched off with a delay of approx. 2 minutes after the doors are closed. The light goes out immediately as soon as the ignition is switched on or the vehicle is locked.

Orientation light:
A light-emitting diode at the bottom of the interior mirror improves orientation in the passenger compartment when it is dark.

Note on operation:
On vehicles with the Sport Chrono Package Plus,
the brightness of the orientation light can be
changed in PCM.

Looks like only the orientation light settings can be changed. Sorry about that.

CORSASCHNELL

Back to the original problem, this light staying on for 2 minutes more or less should not drain a 1 year old battery. I think you either had a defective battery or not driving the car very frequently. My Indy mechanic tells me if a modern 911 is not driven for more than 10 days, one should seriously consider a battery maintainer (aka trickle charger) or face changing batteries frequently.

ELUSIVE

I do this now since I had some battery issues a few years ago stemming from my Tooki Bluetooth module. My car is always locked.
Do you have any aftermarket accessories installed that could be causing the drain?

Battery maintainer is also highly recommended.