Battery keeps dying - Electrical drain

[JoeA]

I just replaced my battery and I am finding as of late something is causing my battery to drain, this most likely caused me to think it was my last battery going dead, so i shelled out the $70.00 and bought a new one.

Specs: I have added nothing new, the battery does charge from the engine, I am showing good levels on my indicators, so I have no clue what is causing this.

Obvious thoughts: I am not leaving the door open, the only thing I suspect is the alarm system, however, I am not sure. It is all stock electronics.

Anyone have any ideas?

Joe

[Loren]

When you set the alarm do you hear a chirp?

Another likely cause is the light in the front trunk... actually the microswitch that turns it off. Try taking the bulb out and see if that helps - if so, then it is the microswitch.

[JoeA]

The Battery has been out on the trunk for a long time, I mean literally out. Do you have a MOP for the microswitch replacement or is that a dealer kind of thing?

I do not hear a chirp when I activate the alarm, only the flashing lights and the signal indicator (flashing red light)

[Loren]

The microswitch is in the front latch mechanism. A couple folks have covered the latch replacement here already. The switch is 996 613 206 00 - retails for $61.47. That's an obscene price - talk to the folks at Sunset Imports (Porsche Parts ar Dealer Cost) - I'm sure they can do better.

[JoeA]

The microswitch is in the front latch mechanism. A couple folks have covered the latch replacement here already. The switch is 996 613 206 00 - retails for $61.47. That's an obscene price - talk to the folks at Sunset Imports (Porsche Parts ar Dealer Cost) - I'm sure they can do better.

<{POST_SNAPBACK}>

Loren,

I really appreciate the advice, is there any way to verify the problem is indeed the microswitch?

Joe

[Loren]

Try taking the bulb out and see if that helps with the power drain - if so, then it is the microswitch.

[JoeA]

Try taking the bulb out and see if that helps with the power drain - if so, then it is the microswitch.

<{POST_SNAPBACK}>

Bulb has not been there in ages? Could it still be the Microswitch?

[Loren]

Probably not - no bulb no drain.

About the only home remedy I can think of is pull one fuse at a time and try to find the circuit with the drain that way.

[JoeA]

Ok, Now I am really stuck, used test light and removed every fuse one by one, - remove, check test light, replace remove the next one and so on. HELP!!!! Battery still draining and None of the fuses removed turned the light off,

I even did this with the doors closed, tried to emulate what condition the car is in when parked.

Any other ideas on what this is?

[ar38070]

With the car off, the key out of the ignition, trunks closed, no lights on, the drain on the battery from the alarm system, etc. is about 50ma. Hook an ammeter in series with the positive lead to see if that is true. If it is more than that then you can try pulling fuses. However if you have a short some place before the fuse box that wont find it.

[JoeA]

Ok silly question, I pulled the negative lead off and jumped the negative lead to the battery with the test light, then started pulling each fuse individually and putting them back looking each time to see if the light went out, should it have been the positive lead?

[Danyol]

-Ve lead is ok for current measurement, although I think AR was referring to using a amp meter. This would provide an absolute value.

So the light stayed on through removing every fuse, didn't dim at any point?

[1999Porsche911]

:oops: Error.

Edited September 10, 2005 by 1999Porsche911

[ar38070]

Ok silly question, I pulled the negative lead off and jumped the negative lead to the battery with the test light, then started pulling each fuse individually and putting them back looking each time to see if the light went out, should it have been the positive lead?

<{POST_SNAPBACK}>

I do not know what kind of light you were using but there are probably several circuits active when the car is "off". So unless you pulled all of the fuses all at the same time the light would never go off. I would use an ammeter (amp meter) to see exactly how much current is being drawn.

I do not believe it matters if you use the negative lead or the positive lead. Electric current is electric current.

[JoeA]

Agreed, so based on what we know, what should be the draw on the car's battery when the car is off and the alarm is activated, hell or inactive. Can someone take a reading and let me know?

Then i will go out again and give it a shot

Joe

[ar38070]

On my car (98 boxster) with the key out of the ignition, unlocked, hood closed, no interior lights I read 100-110 ma. If I arm the alarm I read 125-150 ma.

On my car when you disconnect the battery, hook up the ammeter i.e. reconnect the battery, the car does not seem to wake up i.e. for example the trunk light does not come on right away. The ammeter reading is very low, 10-20 ma. You have to open the door or something before trunk light will come on.

[JoeA]

Well some time you go over to your Dad's and he pulls out an old battery check unit, while the car is running he hooks it up, the indicator for the charging system i.e. alternator says low. Could it be the alternator? Will it still appear to be charging , about 13.5 on the voltage indicator inside the car and the alternator still be bad? I tried the old, disconnect the battery while the car is running trick, no guidance there.

Today was fun trying to find a good volt meter, no luck, and then concluding it could be the alternator on not being sure. Might just hand it over to RPM Racing and have them check it over, although I would like to nail this.

If it is the alternator has anyone changed it out? is it harder then your average alternator on say a 350 chevy?

So it is either the alternator or i need to keep digging? thoguhts?

[JoeA]

OK, Shop has had the car for 3 weeks. They checked the alternator, pulled fuses, car is still draining, I guess it would be time to bite the bullet, take it from the shop and take it to Porsche.

Does anyone have any other ideas before hand?

Joe

The big question is, the Shop has been looking into it without a fix, do they get paid for any of that work if the problem is not fixed?

Edited October 15, 2005 by JoeA

[Loren]

You have checked and/or cleaned all the major ground straps right... ?

[JoeA]

Nope - Did not check those, do you have any information on the ground straps?

Joe

[rattles]

Nope - Did not check those, do you have any information on the ground straps?

Joe

<{POST_SNAPBACK}>

Just a thought, I understand US models have the cigarette lighter powered even if the ignition is off, might be worth checking that its not somehow been pushed in and stuck in the on position.

[Loren]

Nope - Did not check those, do you have any information on the ground straps?

Joe

I would start with the body to engine ground strap (GP14).

[Stefan]

Did you check the current flow across all of the fuses with an ammeter? This would tell you which circuit is causing the drain.