Battery Drain

augsburg911 · 07-03-2009, 09:43 PM

I was speaking to a family member of mine who also owns a 964, and he has experienced the same problem with his car, that I am having with mine. The battery will drain down, and not kick over, if parked for 2 or more days. When I turn my car off I hear a faint humming sound. I believe it might be from the after market stereo system, put in by the PO. I am going to use a battery test light to see if this is the problem. My question, has anyone experienced a battery drain (car not starting) after being parked for a few days?

dfinnegan · 07-03-2009, 11:28 PM

You may be hearing the CCU temperature sensor fan. That has been known to fail in the "on" mode. Try pulling that fuse.

augsburg911 · 07-03-2009, 11:48 PM

Thanks, I'll give it a try.

Smokin · 07-04-2009, 12:49 AM

There are a lot of reasons for battery drain. A search here will turn up plenty... How old is your battery?

I was irked a few months ago because my Optima battery was needing a topping off every few days. I keep a battery tender on it but I thought I had just replaced it 2 years before and I couldn't believe it was the battery so I started looking elsewhere. I checked my receipt for the battery and it was 5 years old! I took it back and got a partial refund against a new one and now I don't have a problem unless I let it sit for over two to three weeks.

groovzilla · 07-04-2009, 02:39 AM

since i just experienced this with my car i thought i should mention:

1. check the interior door light switches in both pillars...are the lights comming on when door is open?...if not they could be shorting...
...same is true for front trunk and front hood light switches

**front hood switch also rests against a small piece of metal when hood is shut and sometimes this piece of metal gets bent downward and does not turn the light off....replacing the pillar switches cured my drain problem..

2. there are several threads about checking draw on battery and you should check that also to help determine source using a difital ampmeter...

newsboy · 07-04-2009, 08:22 AM

You don't say how old your battery is. You can take it to Sears, and they will test it for you to determine if it needs replacement.

augsburg911 · 07-04-2009, 06:29 PM

Thanks for all your suggestions, I will give them a try. The battery was manufactured 0n 05/2008. I purchsaed a new one, and now I leave the negative cable off, until I can figure what the cause of the drain is from.

Marc Shaw · 07-04-2009, 10:28 PM

Quote:

Originally Posted by Smokin

There are a lot of reasons for battery drain. A search here will turn up plenty... How old is your battery?

I was irked a few months ago because my Optima battery was needing a topping off every few days. I keep a battery tender on it but I thought I had just replaced it 2 years before and I couldn't believe it was the battery so I started looking elsewhere. I checked my receipt for the battery and it was 5 years old! I took it back and got a partial refund against a new one and now I don't have a problem unless I let it sit for over two to three weeks.

What a coincidence - I just got back from WallyMart buying another Optima Red 35/75 to replace mine from 2005 as it would no longer hold a charge -- even with a trickle charger on all the time.

Marc

07-03-2009, 09:43 PM	#1
augsburg911 User Join Date: Apr 2009 Posts: 78	Battery Drain I was speaking to a family member of mine who also owns a 964, and he has experienced the same problem with his car, that I am having with mine. The battery will drain down, and not kick over, if parked for 2 or more days. When I turn my car off I hear a faint humming sound. I believe it might be from the after market stereo system, put in by the PO. I am going to use a battery test light to see if this is the problem. My question, has anyone experienced a battery drain (car not starting) after being parked for a few days? Last edited by augsburg911; 07-03-2009 at 10:49 PM.

07-03-2009, 11:28 PM	#2
dfinnegan Addict Rennlist Member Join Date: Jul 2005 Location: NY, USA Posts: 2,908	You may be hearing the CCU temperature sensor fan. That has been known to fail in the "on" mode. Try pulling that fuse. __________________ 1991 C4 Coupe, Polar Silver The hours a Porsche spends parked. You don't get those back. Last edited by dfinnegan; 07-03-2009 at 11:42 PM. Reason: CCU not ECU!

07-04-2009, 12:49 AM	#4
Smokin Addict Rennlist Member Join Date: Oct 2002 Location: Pasadena, MD - Land of Taxes Posts: 1,855	There are a lot of reasons for battery drain. A search here will turn up plenty... How old is your battery? I was irked a few months ago because my Optima battery was needing a topping off every few days. I keep a battery tender on it but I thought I had just replaced it 2 years before and I couldn't believe it was the battery so I started looking elsewhere. I checked my receipt for the battery and it was 5 years old! I took it back and got a partial refund against a new one and now I don't have a problem unless I let it sit for over two to three weeks. __________________ Rick 1990 C2 - Guards Red - Smokin Engine by Andial - Custom "JA" Chip - Sport Muffler - Cat Bypass - Bilstein Shocks - H&R Springs - Big Reds - Club Sport LWF 2006 Hummer H3 2002 BMW 325xi Priors... 77 Porsche 911S Targa 64 Triumph TR4

07-04-2009, 02:39 AM	#5
groovzilla Addict Rennlist Member Join Date: Oct 2007 Location: seattle, washington Posts: 486	since i just experienced this with my car i thought i should mention: 1. check the interior door light switches in both pillars...are the lights comming on when door is open?...if not they could be shorting... ...same is true for front trunk and front hood light switches **front hood switch also rests against a small piece of metal when hood is shut and sometimes this piece of metal gets bent downward and does not turn the light off....replacing the pillar switches cured my drain problem.. 2. there are several threads about checking draw on battery and you should check that also to help determine source using a difital ampmeter... __________________ william - 1990 964 C2 coupe.....silver/black - 1959 356A super sunroof...silver/black 1995 993 C2 - polar silver/black - 6 speed - upgraded motor mounts - short shift kit - M030 lowering kit....sold 2009 1996 993 carrera 4 ...........polar silver/black...sold 2008 1979 ferrari 308 ...............red/black...sold...sold 2006 1986-2005...lots of 356's and 911's

07-03-2009, 11:48 PM	#3
augsburg911 User Join Date: Apr 2009 Posts: 78	Thanks, I'll give it a try.

07-04-2009, 08:22 AM	#6
newsboy Addict Rennlist Member Join Date: Aug 2007 Location: Cape Cod, Ma Posts: 289	You don't say how old your battery is. You can take it to Sears, and they will test it for you to determine if it needs replacement.

07-04-2009, 06:29 PM	#7
augsburg911 User Join Date: Apr 2009 Posts: 78	Thanks for all your suggestions, I will give them a try. The battery was manufactured 0n 05/2008. I purchsaed a new one, and now I leave the negative cable off, until I can figure what the cause of the drain is from.