l.chadburn

Hi all
Since owning my car i have always had the issue that if I leave the battery connected I will come to the car and it will be dead. I have resulted into disconnecting the positive terminal whilst it's in the garage and I'm not using it.

Just needs some advice.

Is this ok?
Should I invest in an auto electrician and get this sorted properly?
Anyone had this issue and know the best fix?

Cheers

Lee

Vandit

After you turn off your car and open the door and exit it, do the power windows still work?

mrmandmman

How old is the battery?

ToreB

The 964 shall be able to survive weeks of storage, normal current drain in ignition off is about 25mA.
A 4-5 year old battery might be due to exchange, and you could measure the current draw from the battery in ignition off.
All the best,
Tore

J richard

If you have a secure garage charge up the battery and just leave it unlocked. Locked my battery lasts two weeks, unlocked a month and a half. The Porsche security system sucks in so many ways....

deadendd9009

Mine does this!

Richard Curtis

Might be fair to say that we've all had this problem. There could be any number of current-drain culprits: glove compartment light? Frunk light? Engine compartment light? Stuck door switches? You should be able to find online the procedure for tracking down the drain issues. You will need a multimeter. Search is your friend.

Vegas993

New door switches fixed my drain.

l.chadburn

Thanks for the replies guys.

Vandit - The Windows don't still work once the ignition is off.

The battery is only a year old.

Did the door switches a few years back, no change.

I think I might get an auto electrician to have a look.

Lee

Jacke2c

do the interior lights come on as you open the door? That is the circuit that tells the computer that it can shut down all systems. As long as the light is off after shutting down the system and you have not opened the door, the computer is active and keeps all systems live/working. once you open the door and the light comes on, it signals the computer to shut down all systems. An intermittent light switch gives exactly the same results as you are describing.

ToreB

turbotwoshoes, this is not entirely correct. There are several computer controlled systems in the 964, and the door lock/alarm control module only is affected by the door switches, as well as the relay for the power windows/sunroof and interior lights. This also depends on 964 model, either with the older door lock or the newer door lock/alarm control module.
All other control modules shall shut down with ignition off.
I.chadburn, you could tell your electrician to measure the current draw at ignition off. (disconnect battery before measuring to ensure that the Climate Control Module (CCU) is off) If the current is above 25-40mA, try to isolate the circuit in question by pulling the fuses one by one.

The CCU has a known problem, an internal transistor can fail, keeping the unit active after ignition off. It shall shut down within max 20 minutes. Fixing this is easy for a guy with some electronics knowledge and experience with a soldering iron.
Cheers,
Tore

NoSub Dan

I wired my dome light backwards and had a Hell of a time finding where the power drain was coming from. The dome is connected to the clock is connected to the radio! Good luck.